7559 - reorganize sectors built in raw hex
This was tedious for three reasons beyond the usual one of having to
track and update offsets several time while I debug:
- The Bochs troubles of the previous commit kept polluting my brain
even though they were irrelevant.
- I had to keep some changes locally to allow myself to use Bochs,
which polluted my working directory.
- I had to travel the long way to the realization that I'm not
actually initializing the stack anywhere. BIOS was starting my stack
off at 0x10000, which was promptly clobbered by my second read from
disk.
The good news: while I'm here I grow the interrupt descriptor table. So
I don't have to go through this exercise when I get back to supporting
the mouse.
This commit is contained in:
Kartik Agaram
parent
1c77be68d7
commit
3844651e49
Binary file not shown.
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@ -7,7 +7,7 @@
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#
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# The expected input is a stream of bytes and some interspersed labels.
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# Comments and '==' segment headers are allowed, but ignored. The emitted code
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# will all lie in a single header, and start at address 0x9000.
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# will all lie in a single header, and start at address 0x9400.
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# $ cat x
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# == code
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# l1:
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@ -197,7 +197,7 @@ test-subx-survey-computes-addresses:
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# 01
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#
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# trace contains (in any order):
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# label x is at address 0x9005
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# label x is at address 0x9405
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#
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# . prologue
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55/push-ebp
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@ -315,10 +315,10 @@ test-subx-survey-computes-addresses:
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#? # . . discard args
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#? 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
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#? # }}}
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# . check-trace-contains("label 'x' is at address 0x00009005.", msg)
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# . check-trace-contains("label 'x' is at address 0x00009405.", msg)
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# . . push args
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68/push "F - test-subx-survey-computes-addresses/0"/imm32
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68/push "label 'x' is at address 0x00009005."/imm32
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68/push "label 'x' is at address 0x00009405."/imm32
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# . . call
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e8/call check-trace-contains/disp32
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# . . discard args
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@ -330,7 +330,7 @@ test-subx-survey-computes-addresses:
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compute-offsets: # in: (addr stream byte), labels: (addr stream {(handle array byte), address})
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# pseudocode:
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# var current-address = 0x9000
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# var current-address = 0x9400
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# var line: (stream byte 512)
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# while true # line loop
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# clear-stream(line)
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@ -362,8 +362,8 @@ compute-offsets: # in: (addr stream byte), labels: (addr stream {(handle array
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53/push-ebx
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56/push-esi
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57/push-edi
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# var current-address/esi: int = 0x9000
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be/copy-to-esi 0x9000/imm32
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# var current-address/esi: int = 0x9400
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be/copy-to-esi 0x9400/imm32
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# var line/ecx: (stream byte 512)
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81 5/subop/subtract 3/mod/direct 4/rm32/esp . . . . . 0x200/imm32 # subtract from esp
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68/push 0x200/imm32/size
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@ -595,7 +595,7 @@ test-compute-offsets:
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# 34
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#
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# trace contains (in any order):
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# label 'x' is at address 0x9006.
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# label 'x' is at address 0x9406.
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#
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# . prologue
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55/push-ebp
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@ -697,10 +697,10 @@ test-compute-offsets:
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#? # . . discard args
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#? 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
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#? # }}}
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# . check-trace-contains("label 'x' is at address 0x00009006.", msg)
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# . check-trace-contains("label 'x' is at address 0x00009406.", msg)
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# . . push args
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68/push "F - test-compute-offsets"/imm32
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68/push "label 'x' is at address 0x00009006."/imm32
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68/push "label 'x' is at address 0x00009406."/imm32
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# . . call
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e8/call check-trace-contains/disp32
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# . . discard args
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@ -732,7 +732,7 @@ emit-output:datum: # slice
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emit-output: # in: (addr stream byte), out: (addr buffered-file), labels: (addr stream {(handle array byte), address})
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# pseudocode:
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# var address-of-next-instruction = 0x9000
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# var address-of-next-instruction = 0x9400
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# var line: (stream byte 512)
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# line-loop:
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# while true
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@ -803,8 +803,8 @@ emit-output: # in: (addr stream byte), out: (addr buffered-file), labels: (addr
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68/push 0/imm32/end
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68/push 0/imm32/start
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89/copy 3/mod/direct 2/rm32/edx . . . 4/r32/esp . . # copy esp to edx
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# var address-of-next-instruction/ebx = 0x9000
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bb/copy-to-ebx 0x9000/imm32
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# var address-of-next-instruction/ebx = 0x9400
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bb/copy-to-ebx 0x9400/imm32
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$emit-output:line-loop:
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# clear-stream(line)
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# . . push args
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@ -1491,12 +1491,12 @@ test-emit-output-code-label:
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# ef gh
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# e8 l1/disp32
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# labels:
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# - 'l1': 0x9010
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# - 'l1': 0x9410
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#
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# output:
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# ab cd
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# ef gh
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# e8 07 00 00 00 # 0x9010 - 0x9009 = 7
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# e8 07 00 00 00 # 0x9410 - 0x9409 = 7
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#
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# . prologue
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55/push-ebp
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@ -1566,8 +1566,8 @@ test-emit-output-code-label:
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e8/call write/disp32
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# . . discard args
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81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
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# . stream-add2(labels, "l1", 0x9010)
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68/push 0x9010/imm32/label-address
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# . stream-add2(labels, "l1", 0x9410)
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68/push 0x9410/imm32/label-address
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# . . push handle for "l1"
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53/push-ebx
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68/push "l1"/imm32
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@ -28,7 +28,7 @@ pixel-on-real-screen: # x: int, y: int, color: int
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c1/shift 4/subop/left %eax 0xa/imm8
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03/add-> *(ebp+8) 0/r32/eax
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# eax += location of frame buffer
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03/add-> *0x7e28 0/r32/eax # unsafe
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03/add-> *0x7f28 0/r32/eax # unsafe
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# *eax = color
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8b/-> *(ebp+0x10) 1/r32/ecx
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88/byte<- *eax 1/r32/CL
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@ -20,19 +20,19 @@ read-key: # kbd: (addr keyboard) -> result/eax: byte
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{
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75/jump-if-!= break/disp8
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# var read/ecx: byte = keyboard buffer's read index
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8b/-> *0x7dcc 1/r32/CL # keyboard-buffer-read
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8b/-> *0x7ee4 1/r32/CL # keyboard-buffer-read
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# var next-key/eax: byte = *(keyboard buffer + ecx)
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8a/byte-> *(ecx+0x7dd0) 0/r32/AL # keyboard-buffer-data
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# if (next-key != 0) lock and remove from keyboard-buffer
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8a/byte-> *(ecx+0x7ee8) 0/r32/AL # keyboard-buffer-data
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# if (next-key != 0) lock and remove from keyboard buffer
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81 7/subop/compare %eax 0/imm32
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{
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74/jump-if-= break/disp8
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# TODO: add some instructions in this block to SubX if we ever want to
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# use bootstrap on baremetal programs
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fa/disable-interrupts
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c6 0/subop/copy-byte *(ecx+0x7dd0) 0/imm8
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ff 0/subop/increment *0x7dcc # keyboard-buffer-read
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81 4/subop/and *0x7dcc 0xf/imm32 # keyboard-buffer-read
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c6 0/subop/copy-byte *(ecx+0x7ee8) 0/imm8 # keyboard-buffer-data
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ff 0/subop/increment *0x7ee4 # keyboard-buffer-read
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81 4/subop/and *0x7ee4 0xf/imm32 # keyboard-buffer-read
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fb/enable-interrupts
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}
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# return
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@ -25,9 +25,9 @@ draw-grapheme-on-real-screen: # g: grapheme, x: int, y: int, color: int, backgr
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# var letter-bitmap/esi = font[g]
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8b/-> *(ebp+8) 6/r32/esi
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c1 4/subop/shift-left %esi 4/imm8
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8d/copy-address *(esi+0x8800) 6/r32/esi # font-start
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# if (letter-bitmap >= 0x9000) return # characters beyond ASCII currently not supported
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81 7/subop/compare %esi 0x9000/imm32
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8d/copy-address *(esi+0x8c00) 6/r32/esi # font-start
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# if (letter-bitmap >= 0x9400) return # characters beyond ASCII currently not supported
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81 7/subop/compare %esi 0x9400/imm32
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7d/jump-if->= $draw-grapheme-on-real-screen:end/disp8
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# var ycurr/edx: int = y*16
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8b/-> *(ebp+0x10) 2/r32/edx
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@ -30,7 +30,7 @@ operating systems. There's also currently no code/data segment separation,
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just labels and bytes. I promise not to write self-modifying code. Security
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and sandboxing is still an open question.
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Programs start executing at address 0x9000. See baremetal/boot.hex for
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Programs start executing at address 0x9400. See baremetal/boot.hex for
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details.
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Mu programs always run all their automated tests first. `main` only runs if
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@ -24,7 +24,7 @@
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# This file contains just lowercase hex bytes and comments. Zero
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# error-checking. Make liberal use of:
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# - comments documenting expected offsets
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# - size checks on the emitted file (currently: 5120 bytes)
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# - size checks on the emitted file (currently: 6144 bytes)
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# - xxd to eyeball that offsets contain expected bytes
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#
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# Programs using this initialization:
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@ -34,20 +34,24 @@
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# - must start executing immediately after this file (see outline below)
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# Outline of this file with offsets and the addresses they map to at run-time:
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# offset 0 (address 7c00): boot code, 16-bit mode
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# 80 (address 7c80) global descriptor table
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# a0 (address 7ca0) <== gdt_descriptor
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# offset e0 (address 7ce0): boot code
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# offset 100 (address 7d00): interrupt handler code
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# 1c8 (address 7dc8) <== keyboard buffer
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# 1f8 (address 7df8) <== idt_descriptor
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# -- 16-bit mode code
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# offset 0 (address 7c00): boot code
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# -- 16-bit mode data
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# e0 (address 7c80) global descriptor table
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# f8 (address 7ca0) <== gdt_descriptor
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# -- 32-bit mode code
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# offset 100 (address 7d00): boot code
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# 1fe (address 7dfe) boot sector marker (2 bytes)
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# offset 200 (address 7e00): video mode data (256 bytes)
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# 228 (address 7e28) <== start of video RAM stored here
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# offset 300 (address 7f00): interrupt descriptor table (256 bytes)
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# offset 400 (address 8000): keyboard mappings (2KB)
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# offset c00 (address 8800): bitmap font (2KB)
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# offset 1400 (address 9000): entrypoint for applications (don't forget to adjust survey_baremetal if this changes)
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# offset 200 (address 7e00): interrupt handler code
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# -- 32-bit mode data
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# 2e0 (address 7ee0) <== keyboard buffer
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# 2f8 (address 7ef8) <== idt_descriptor
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# offset 300 (address 7f00): video mode data (256 bytes)
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# 328 (address 7f28) <== start of video RAM stored here
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# offset 400 (address 8000): interrupt descriptor table (1KB)
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# offset 800 (address 8400): keyboard mappings (2KB)
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# offset 1000 (address 8c00): bitmap font (2KB)
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# offset 1800 (address 9400): entrypoint for applications (don't forget to adjust survey_baremetal if this changes)
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## 16-bit entry point
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@ -90,7 +94,7 @@
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cd 13 # int 13h, BIOS disk service
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0f 82 8a 00 # jump-if-carry disk_error [label]
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# 26:
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# load 63 sectors from disk into addresses [0xfa00, 0x17800)
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# load second track from disk into addresses [0xfa00, 0x17800)
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b4 02 # ah <- 2 # read sectors from disk
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b5 00 # ch <- 0 # cylinder 0
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b6 01 # dh <- 1 # track 1
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@ -145,21 +149,48 @@
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b4 4f # ah <- 4f (VBE)
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b0 01 # al <- 01 (get video mode)
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b9 07 01 # cx <- 0x0107 (mode we requested)
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bf 00 7e # di <- 0x7e00 (video mode info) [label]
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bf 00 7f # di <- 0x7f00 (video mode info) [label]
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cd 10
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# 6c:
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# switch to 32-bit mode
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0f 01 16 # lgdt 00/mod/indirect 010/subop 110/rm/use-disp16
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a0 7c # *gdt_descriptor [label]
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f8 7c # *gdt_descriptor [label]
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0f 20 c0 # eax <- cr0
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66 83 c8 01 # eax <- or 0x1
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0f 22 c0 # cr0 <- eax
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ea e0 7c 08 00 # far jump to initialize_32bit_mode after setting cs to the record at offset 8 in the gdt (gdt_code) [label]
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ea 00 7d 08 00 # far jump to initialize_32bit_mode after setting cs to the record at offset 8 in the gdt (gdt_code) [label]
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# padding
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# 80:
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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# cf:
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# disk_error:
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# print 'D' to top-left of screen to indicate disk error
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# *0xb8000 <- 0x0f44
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# bx <- 0xb800
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bb 00 b8
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# ds <- bx
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8e db # 11b/mod 011b/reg/ds 011b/rm/bx
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# al <- 'D'
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b0 44
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# ah <- 0x0f # white on black
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b4 0f
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# bx <- 0
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bb 00 00
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# *ds:bx <- ax
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89 07 # 00b/mod/indirect 000b/reg/ax 111b/rm/bx
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e9 fd ff # loop forever
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## GDT: 3 records of 8 bytes each
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# 80:
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# e0:
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# gdt_start:
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# gdt_null: mandatory null descriptor
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00 00 00 00 00 00 00 00
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@ -180,46 +211,18 @@
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00 # base[24:32]
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# gdt_end:
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# padding
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# 98:
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00 00 00 00 00 00 00 00
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# a0:
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# f8:
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# gdt_descriptor:
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17 00 # final index of gdt = gdt_end - gdt_start - 1
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80 7c 00 00 # start = gdt_start [label]
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e0 7c 00 00 # start = gdt_start [label]
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# padding
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# a5:
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00 00 00 00 00 00 00 00 00 00
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# b0:
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# disk_error:
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# print 'D' to top-left of screen to indicate disk error
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# *0xb8000 <- 0x0f44
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# bx <- 0xb800
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bb 00 b8
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# ds <- bx
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8e db # 11b/mod 011b/reg/ds 011b/rm/bx
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# al <- 'D'
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b0 44
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# ah <- 0x0f # white on black
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b4 0f
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# bx <- 0
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bb 00 00
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# *ds:bx <- ax
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89 07 # 00b/mod/indirect 000b/reg/ax 111b/rm/bx
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e9 fd ff # loop forever
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# padding
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# c1:
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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# fe:
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00 00
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## 32-bit code from this point (still some instructions not in SubX)
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# e0:
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# offset 100 (address 0x7d00):
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# initialize_32bit_mode:
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66 b8 10 00 # ax <- offset 16 from gdt_start
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8e d8 # ds <- ax
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@ -228,9 +231,10 @@ e9 fd ff # loop forever
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8e e0 # fs <- ax
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8e e8 # gs <- ax
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# 10e:
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# load interrupt handlers
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0f 01 1d # lidt 00/mod/indirect 011/subop 101/rm32/use-disp32
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f8 7d 00 00 # *idt_descriptor [label]
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f8 7e 00 00 # *idt_descriptor [label]
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# For now, not bothering reprogramming the IRQ to not conflict with software
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# exceptions.
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@ -241,27 +245,49 @@ e9 fd ff # loop forever
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# Reference:
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# https://wiki.osdev.org/Exceptions
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# 115:
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# enable keyboard IRQ (1)
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b0 fd # al <- 0xfd # disable mask for IRQ1
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e6 21 # port 0x21 <- al
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# 119:
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# initialization is done; enable interrupts
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fb
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e9 01 13 00 00 # jump to 0x9000 [label]
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e9 e1 16 00 00 # jump to 0x9400 [label]
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# padding
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# ff:
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# 11f:
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00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
||||
# 100:
|
||||
# 1fe:
|
||||
# final 2 bytes of boot sector
|
||||
55 aa
|
||||
|
||||
## sector 2 onwards loaded by load_disk, not automatically on boot
|
||||
|
||||
# offset 200 (address 0x7e00):
|
||||
# null interrupt handler:
|
||||
cf # iret
|
||||
|
||||
# padding
|
||||
# 101:
|
||||
# 201:
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
||||
# 110:
|
||||
# 210:
|
||||
# keyboard interrupt handler:
|
||||
# prologue
|
||||
fa # disable interrupts
|
||||
|
|
@ -276,20 +302,20 @@ e9 fd ff # loop forever
|
|||
24 01 # al <- and 0x1
|
||||
3c 00 # compare al, 0
|
||||
74 39 # jump to epilogue if = [label]
|
||||
# 120:
|
||||
# 220:
|
||||
# if keyboard buffer is full, return
|
||||
31 c9 # ecx <- xor ecx; 11/direct 001/r32/ecx 001/rm32/ecx
|
||||
# . var index/ecx: byte
|
||||
8a # copy m8 at r32 to r8
|
||||
0d # 00/mod/indirect 001/r8/cl 101/rm32/use-disp32
|
||||
c8 7d 00 00 # disp32 [label]
|
||||
e0 7e 00 00 # disp32 [label]
|
||||
# . al = *(keyboard buffer + index)
|
||||
8a # copy m8 at r32 to r8
|
||||
81 # 10/mod/*+disp32 000/r8/al 001/rm32/ecx
|
||||
d0 7d 00 00 # disp32 [label]
|
||||
e8 7e 00 00 # disp32 [label]
|
||||
# . if (al != 0) return
|
||||
3c 00 # compare al, 0
|
||||
# 130:
|
||||
# 230:
|
||||
75 27 # jump to epilogue if != [label]
|
||||
# read keycode into al
|
||||
e4 60 # al <- port 0x60
|
||||
|
|
@ -299,37 +325,37 @@ e9 fd ff # loop forever
|
|||
3c 00 # compare al, 0
|
||||
58 # pop to eax (without touching flags)
|
||||
75 1d # jump to epilogue if != [label]
|
||||
# 13c:
|
||||
# 23c:
|
||||
# al <- *(keyboard normal map + eax)
|
||||
8a # copy m8 at rm32 to r8
|
||||
80 # 10/mod/*+disp32 000/r8/al 000/rm32/eax
|
||||
00 80 00 00 # disp32 [label]
|
||||
00 84 00 00 # disp32 [label]
|
||||
# if there's no character mapping, return
|
||||
3c 00 # compare al, 0
|
||||
74 13 # jump to epilogue if = [label]
|
||||
# 146:
|
||||
# 246:
|
||||
# store al in keyboard buffer
|
||||
88 # copy r8 to m8 at r32
|
||||
81 # 10/mod/*+disp32 000/r8/al 001/rm32/ecx
|
||||
d0 7d 00 00 # disp32 [label]
|
||||
# 14c:
|
||||
e8 7e 00 00 # disp32 [label]
|
||||
# 24c:
|
||||
# increment index
|
||||
fe # increment byte
|
||||
05 # 00/mod/indirect 000/subop/increment 101/rm32/use-disp32
|
||||
c8 7d 00 00 # disp32 [label]
|
||||
e0 7e 00 00 # disp32 [label]
|
||||
# clear top nibble of index (keyboard buffer is circular)
|
||||
80 # and byte
|
||||
25 # 00/mod/indirect 100/subop/and 101/rm32/use-disp32
|
||||
c8 7d 00 00 # disp32 [label]
|
||||
e0 7e 00 00 # disp32 [label]
|
||||
0f # imm8
|
||||
# 159:
|
||||
# 259:
|
||||
# epilogue
|
||||
61 # pop all registers
|
||||
fb # enable interrupts
|
||||
cf # iret
|
||||
|
||||
# padding
|
||||
# 15c:
|
||||
# 25c:
|
||||
00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -337,76 +363,69 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
||||
# 1c8:
|
||||
# 2e0:
|
||||
# var keyboard circular buffer
|
||||
# write index: nibble
|
||||
# still take up 4 bytes so SubX can handle it
|
||||
00 00 00 00
|
||||
# 1cc:
|
||||
# 2e4:
|
||||
# read index: nibble
|
||||
# still take up 4 bytes so SubX can handle it
|
||||
00 00 00 00
|
||||
# 1d0:
|
||||
# 2e8:
|
||||
# circular buffer: byte[16]
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
||||
# padding
|
||||
# 1e0:
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
|
||||
# 1f8:
|
||||
# 2f8:
|
||||
# idt_descriptor:
|
||||
ff 00 # idt_end - idt_start - 1
|
||||
00 7f 00 00 # start = idt_start [label]
|
||||
00 80 00 00 # start = idt_start [label]
|
||||
|
||||
# 1fe:
|
||||
# final 2 bytes of boot sector
|
||||
55 aa
|
||||
# padding
|
||||
# 2fe:
|
||||
00 00
|
||||
|
||||
## sector 2
|
||||
# loaded by load_disk, not automatically on boot
|
||||
|
||||
# offset 200 (address 0x7e00):
|
||||
# offset 300 (address 0x7f00):
|
||||
# video mode info:
|
||||
00 00 # attributes
|
||||
00 # winA
|
||||
00 # winB
|
||||
# 204
|
||||
# 304
|
||||
00 00 # granularity
|
||||
00 00 # winsize
|
||||
# 208
|
||||
# 308
|
||||
00 00 # segmentA
|
||||
00 00 # segmentB
|
||||
# 20c
|
||||
# 30c
|
||||
00 00 00 00 # realFctPtr (who knows)
|
||||
# 210
|
||||
# 310
|
||||
00 00 # pitch
|
||||
00 00 # Xres
|
||||
# 214
|
||||
# 314
|
||||
00 00 # Yres
|
||||
00 00 # Wchar Ychar
|
||||
# 218
|
||||
# 318
|
||||
00 # planes
|
||||
00 # bpp
|
||||
00 # banks
|
||||
00 # memory_model
|
||||
# 21c
|
||||
# 31c
|
||||
00 # bank_size
|
||||
00 # image_pages
|
||||
00 # reserved
|
||||
# 21f
|
||||
# 31f
|
||||
00 00 # red_mask red_position
|
||||
00 00 # green_mask green_position
|
||||
00 00 # blue_mask blue_position
|
||||
00 00 # rsv_mask rsv_position
|
||||
00 # directcolor_attributes
|
||||
# 228
|
||||
# 328
|
||||
00 00 00 00 # physbase <== linear frame buffer
|
||||
|
||||
# 22c
|
||||
# 32c
|
||||
# reserved for video mode info
|
||||
00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -423,8 +442,9 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
||||
# offset 300 (address 0x7f00): interrupt descriptor table
|
||||
# 32 entries * 8 bytes each = 256 bytes (0x100)
|
||||
# offset 400 (address 0x8000):
|
||||
# interrupt descriptor table {{{
|
||||
# 128 entries * 8 bytes each = 1024 bytes (0x400)
|
||||
# idt_start:
|
||||
|
||||
00 00 00 00 00 00 00 00
|
||||
|
|
@ -440,14 +460,14 @@ e9 fd ff # loop forever
|
|||
# https://wiki.osdev.org/index.php?title=Interrupts&oldid=25102#Default_PC_Interrupt_Vector_Assignment
|
||||
|
||||
# entry 8: clock
|
||||
00 7d # target[0:16] = null interrupt handler [label]
|
||||
00 7e # target[0:16] = null interrupt handler [label]
|
||||
08 00 # segment selector (gdt_code)
|
||||
00 # unused
|
||||
8e # 1/p 00/dpl 0 1110/type/32-bit-interrupt-gate
|
||||
00 00 # target[16:32]
|
||||
|
||||
# entry 9: keyboard
|
||||
10 7d # target[0:16] = keyboard interrupt handler [label]
|
||||
10 7e # target[0:16] = keyboard interrupt handler [label]
|
||||
08 00 # segment selector (gdt_code)
|
||||
00 # unused
|
||||
8e # 1/p 00/dpl 0 1110/type/32-bit-interrupt-gate
|
||||
|
|
@ -475,11 +495,114 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
|
||||
# 500:
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
|
||||
# 600:
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
|
||||
# 700:
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00
|
||||
# idt_end:
|
||||
# }}}
|
||||
|
||||
## the rest of this file has data
|
||||
|
||||
# offset 400 (address 0x8000):
|
||||
# offset 800 (address 0x8400):
|
||||
# translating keys to ASCII {{{
|
||||
# keyboard normal map:
|
||||
00
|
||||
|
|
@ -487,22 +610,22 @@ e9 fd ff # loop forever
|
|||
1b
|
||||
# |<--- digits -------------->| - = bs
|
||||
31 32 33 34 35 36 37 38 39 30 2d 3d 08
|
||||
# offset 40f
|
||||
# offset 80f
|
||||
# tb q w e r t y u i o p [ ]
|
||||
09 71 77 65 72 74 79 75 69 6f 70 5b 5d
|
||||
# offset 41c
|
||||
# offset 81c
|
||||
# enter
|
||||
0a 00
|
||||
# offset 41e
|
||||
# offset 81e
|
||||
# a s d f g h j k l ; ' ` \
|
||||
61 73 64 66 67 68 6a 6b 6c 3b 27 60 00 5c
|
||||
# offset 42c
|
||||
# offset 82c
|
||||
# z x c v b n m , . / *
|
||||
7a 78 63 76 62 6e 6d 2c 2e 2f 00 2a
|
||||
# offset 438
|
||||
# offset 838
|
||||
# space
|
||||
00 20
|
||||
# offset 43a
|
||||
# offset 83a
|
||||
00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -517,7 +640,7 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
||||
# 500:
|
||||
# 900:
|
||||
# keyboard shift map:
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -536,7 +659,7 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
||||
# 600:
|
||||
# a00:
|
||||
# keyboard ctrl map:
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -556,7 +679,7 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
||||
# padding (there might be more keyboard tables)
|
||||
# 700:
|
||||
# b00:
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -573,8 +696,7 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
||||
# 800:
|
||||
# c00:
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -591,6 +713,7 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
# d00:
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -607,7 +730,7 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
# a00:
|
||||
# e00:
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -624,6 +747,7 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
# f00:
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
|
|
@ -642,7 +766,7 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
# }}}
|
||||
|
||||
# offset c00 (address 0x8800)
|
||||
# offset 1000 (address 0x8c00)
|
||||
# Bitmaps for some ASCII characters (soon Unicode) {{{
|
||||
# Part of GNU Unifont
|
||||
# 8px wide, 16px tall
|
||||
|
|
@ -880,6 +1004,6 @@ e9 fd ff # loop forever
|
|||
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
|
||||
# }}}
|
||||
|
||||
# offset 1400 (address 0x9000)
|
||||
# offset 1800 (address 0x9400)
|
||||
|
||||
# vim:ft=subx
|
||||
|
|
|
|||
|
|
@ -18,7 +18,7 @@
|
|||
# ecx <- LFB
|
||||
8b # copy *rm32 to r32
|
||||
0d # 00/mod/indirect 001/r32/ecx 101/rm32/use-disp32
|
||||
28 7e 00 00 # disp32 [label]
|
||||
28 7f 00 00 # disp32 [label]
|
||||
|
||||
# eax <- LFB + 0xbffff (1024*768 - 1)
|
||||
8d # copy-address rm32 to r32
|
||||
|
|
|
|||
|
|
@ -14,7 +14,7 @@
|
|||
|
||||
main:
|
||||
# ecx <- start of video memory
|
||||
8b/-> *0x7e28 1/r32/ecx
|
||||
8b/-> *0x7f28 1/r32/ecx
|
||||
|
||||
# eax <- final pixel of video memory
|
||||
8d/copy-address *(ecx + 0x0bffff) 0/r32/eax # 0xbffff = 1024*768 - 1
|
||||
|
|
|
|||
|
|
@ -8,6 +8,7 @@
|
|||
|
||||
# initialize stack
|
||||
bd/copy-to-ebp 0/imm32
|
||||
bc/copy-to-esp 0x00070000/imm32 # consult https://wiki.osdev.org/Memory_Map_(x86) when modifying this
|
||||
# always first run tests
|
||||
(run-tests)
|
||||
(num-test-failures) # => eax
|
||||
|
|
|
|||
Loading…
Reference in New Issue