diff options
| -rw-r--r-- | 101screen.subx | 2 | ||||
| -rw-r--r-- | 102keyboard.subx | 17 | ||||
| -rw-r--r-- | 103grapheme.subx | 2 | ||||
| -rw-r--r-- | boot.subx | 77 | ||||
| -rw-r--r-- | ex2.subx | 2 |
5 files changed, 30 insertions, 70 deletions
diff --git a/101screen.subx b/101screen.subx index 46cee777..2aab293d 100644 --- a/101screen.subx +++ b/101screen.subx @@ -28,7 +28,7 @@ pixel-on-real-screen: # x: int, y: int, color: int c1/shift 4/subop/left %eax 0xa/imm8 03/add-> *(ebp+8) 0/r32/eax # eax += location of frame buffer - 03/add-> *0x8128 0/r32/eax # unsafe + 03/add-> *Video-memory-addr 0/r32/eax # *eax = color 8b/-> *(ebp+0x10) 1/r32/ecx 88/byte<- *eax 1/r32/CL diff --git a/102keyboard.subx b/102keyboard.subx index df74c8e7..e8d23962 100644 --- a/102keyboard.subx +++ b/102keyboard.subx @@ -19,20 +19,19 @@ read-key: # kbd: (addr keyboard) -> result/eax: byte 81 7/subop/compare %ecx 0/imm32 { 75/jump-if-!= break/disp8 - # var read/ecx: byte = keyboard buffer's read index - 8b/-> *0x802c 1/r32/CL # keyboard-buffer-read - # var next-key/eax: byte = *(keyboard buffer + ecx) - 8a/byte-> *(ecx+0x8030) 0/r32/AL # keyboard-buffer-data + # var buffer-byte-addr/ecx: (addr byte) + 8b/-> *Keyboard-buffer:read 1/r32/CL + 81 0/subop/add %ecx Keyboard-buffer:data/imm32 + # var next-key/eax: byte = *buffer-byte-addr + 8a/byte-> *ecx 0/r32/AL # if (next-key != 0) lock and remove from keyboard buffer 81 7/subop/compare %eax 0/imm32 { 74/jump-if-= break/disp8 - # TODO: add some instructions in this block to SubX if we ever want to - # use bootstrap on baremetal programs fa/disable-interrupts - c6 0/subop/copy-byte *(ecx+0x8030) 0/imm8 # keyboard-buffer-data - ff 0/subop/increment *0x802c # keyboard-buffer-read - 81 4/subop/and *0x802c 0xf/imm32 # keyboard-buffer-read + c6 0/subop/copy-byte *ecx 0/imm8 + ff 0/subop/increment *Keyboard-buffer:read + 81 4/subop/and *Keyboard-buffer:read 0x0f/imm32 fb/enable-interrupts } # return diff --git a/103grapheme.subx b/103grapheme.subx index 65c5bb2e..ef1f31c9 100644 --- a/103grapheme.subx +++ b/103grapheme.subx @@ -27,7 +27,7 @@ draw-grapheme-on-real-screen: # g: grapheme, x: int, y: int, color: int, backgr # var letter-bitmap/esi = font[g] 8b/-> *(ebp+8) 6/r32/esi c1 4/subop/shift-left %esi 4/imm8 - 8d/copy-address *(esi+0x8c00) 6/r32/esi # font-start + 81 0/subop/add %esi Font/imm32 # if (letter-bitmap >= 0x9400) return # characters beyond ASCII currently not supported 81 7/subop/compare %esi 0x9400/imm32 7d/jump-if->= $draw-grapheme-on-real-screen:end/disp8 diff --git a/boot.subx b/boot.subx index dcca8b2a..38c861bf 100644 --- a/boot.subx +++ b/boot.subx @@ -11,28 +11,7 @@ # - sigils only support 32-bit general-purpose registers, so don't work with segment registers or 16-bit or 8-bit registers # - metadata like rm32 and r32 can sometimes misleadingly refer to only the bottom 16 bits of the register; pay attention to the register name -# Outline of this file with offsets and the addresses they map to at run-time: -# -- 16-bit mode code -# offset 0 (address 7c00): boot code -# -- 16-bit mode data -# e0 (address 7c80) global descriptor table -# f8 (address 7ca0) <== gdt_descriptor -# -- 32-bit mode code -# offset 100 (address 7d00): boot code -# 1fe (address 7dfe) boot-sector-marker (2 bytes) -# offset 200 (address 7e00): interrupt handler code -# -- 32-bit mode data -# offset 400 (address 8000): handler data -# 410 (address 8010): keyboard handler data -# 428 (address 8028) <== keyboard buffer -# offset 500 (address 8100): video mode data (256 bytes) -# 528 (address 8128) <== start of video RAM stored here -# offset 600 (address 8200): interrupt descriptor table (1KB) -# offset a00 (address 8600): keyboard mappings (1.5KB) -# offset 1000 (address 8c00): bitmap font (2KB) -# offset 1800 (address 9400): entrypoint for applications (don't forget to adjust survey_baremetal if this changes) - -# Other details of the current memory map: +# Memory map of a Mu computer: # code: 4 tracks of disk to [0x00007c00, 0x00027400) # stack grows down from 0x00070000 # see below @@ -40,6 +19,9 @@ # see 120allocate.subx # Consult https://wiki.osdev.org/Memory_Map_(x86) before modifying any of this. +# Magic addresses (TODO): +# 0x9400: entrypoint for applications + == code ## 16-bit entry point @@ -298,16 +280,12 @@ keyboard-interrupt-handler: a8/test-bits-in-al 0x01/imm8 # set zf if bit 0 (least significant) is not set 74/jump-if-not-set $keyboard-interrupt-handler:epilogue/disp8 # - if keyboard buffer is full, return - # var index/ecx: byte + # var dest-addr/ecx: (addr byte) = (keyboard-buffer + *keyboard-buffer:write) 31/xor %ecx 1/r32/ecx 8a/byte-> *Keyboard-buffer:write 1/r32/cl -== data - # al = *(keyboard buffer + index) -#? 8a/byte-> *(ecx+Keyboard-buffer:data) 0/r32/al - 8a # copy m8 at r32 to r8 - 81 # 10/mod/*+disp32 000/r8/al 001/rm32/ecx - 30 80 00 00 # disp32 [label] -== code + 81 0/subop/add %ecx Keyboard-buffer:data/imm32 + # al = *dest-addr + 8a/byte-> *ecx 0/r32/al # if (al != 0) return 3c/compare-al-and 0/imm8 75/jump-if-!= $keyboard-interrupt-handler:epilogue/disp8 @@ -374,47 +352,29 @@ keyboard-interrupt-handler: { 81 7/subop/compare *Keyboard-shift-pressed? 0/imm32 74/jump-if-= break/disp8 -== data - # al <- *(keyboard shift map + eax) -#? 8a/byte-> *(eax+Keyboard-shift-map) 0/r32/al - 8a # copy m8 at rm32 to r8 - 80 # 10/mod/*+disp32 000/r8/al 000/rm32/eax - 00 87 00 00 # disp32 [label] -== code + # sigils don't currently support labels inside *(eax+label) + 05/add-to-eax Keyboard-shift-map/imm32 + 8a/byte-> *eax 0/r32/al eb/jump $keyboard-interrupt-handler:select-map-done/disp8 } - # if (ctrl) use keyboard ctrl map + # if (ctrl) al = *(ctrl map + al) { 81 7/subop/compare *Keyboard-ctrl-pressed? 0/imm32 74/jump-if-= break/disp8 -== data - # al <- *(keyboard ctrl map + eax) -#? 8a/byte-> *(eax+Keyboard-shift-map) 0/r32/al - 8a # copy m8 at rm32 to r8 - 80 # 10/mod/*+disp32 000/r8/al 000/rm32/eax - 00 88 00 00 # disp32 [label] -== code + 05/add-to-eax Keyboard-ctrl-map/imm32 + 8a/byte-> *eax 0/r32/al eb/jump $keyboard-interrupt-handler:select-map-done/disp8 } -== data - # otherwise use keyboard normal map - # al <- *(keyboard normal map + eax) -#? 8a/byte-> *(eax+Keyboard-normal-map) 0/r32/al - 8a # copy m8 at rm32 to r8 - 80 # 10/mod/*+disp32 000/r8/al 000/rm32/eax - 00 86 00 00 # disp32 [label] -== code + # otherwise al = *(normal map + al) + 05/add-to-eax Keyboard-normal-map/imm32 + 8a/byte-> *eax 0/r32/al $keyboard-interrupt-handler:select-map-done: # - if there's no character mapping, return { 3c/compare-al-and 0/imm8 74/jump-if-= break/disp8 # - store al in keyboard buffer -== data - 88 # copy r8 to m8 at r32 - 81 # 10/mod/*+disp32 000/r8/al 001/rm32/ecx - 30 80 00 00 # disp32 [label] -== code + 88/<- *ecx 0/r32/al # increment index fe/increment-byte *Keyboard-buffer:write # clear top nibble of index (keyboard buffer is circular) @@ -494,6 +454,7 @@ Video-mode-info: 00 00 # rsv_mask rsv_position 00 # directcolor_attributes # 28 +Video-memory-addr: 00 00 00 00 # physbase <== linear frame buffer # 2c diff --git a/ex2.subx b/ex2.subx index d7809d36..3d91b16f 100644 --- a/ex2.subx +++ b/ex2.subx @@ -11,7 +11,7 @@ main: # ecx <- start of video memory - 8b/-> *0x8128 1/r32/ecx + 8b/-> *Video-memory-addr 1/r32/ecx # eax <- final pixel of video memory 8d/copy-address *(ecx + 0x0bffff) 0/r32/eax # 0xbffff = 1024*768 - 1 |