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Monitor DUMP prints bytes with the standard hex editor layout

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This commit is contained in:
Daniele Verducci su MatissePenguin 2020-12-21 23:12:33 +01:00
parent 43f04da6f1
commit d0afda5c4e
1 changed files with 65 additions and 23 deletions

88
assembly/bios/monitor.asm

@ -76,7 +76,9 @@ monitor_help:
call Print
jp monitor_main_loop
monitor_dump: ; Test with DUMP 0x00A0 (contains text)
; Asks the user for a memory position and shows the following 64 bytes of memory
; @uses a, b, c, d, e, h, l
monitor_dump:
ld bc, MON_COMMAND_DUMP + 1 ; autocomplete command
call Print
; Now read the address from the user
@ -86,36 +88,76 @@ monitor_dump: ; Test with DUMP 0x00A0 (contains text)
; now start displaying bytes from memory
ld e, MON_DUMP_BYTES_LINES ; the number of lines to display
monitor_dump_show_bytes_loop:
ld d, MON_DUMP_BYTES_PER_LINE ; the number of bytes per line to display
ld d, MON_DUMP_BYTES_PER_LINE*2 ; the number of bytes per line to display (*2 as we display two times the same byte: once hex and once ascii)
; Print current address
ld a, h
call monitor_printHexByte
ld a, l
call monitor_printHexByte
; print two spaces
; print four spaces
ld a, 32
call Printc
call Printc
monitor_dump_show_bytes_line_loop:
; print character at mem position
ld a, (hl)
; print hex byte
call monitor_printHexByte
; print space
ld a, 32
call Printc
; print ascii
ld a, (hl)
call monitor_printAsciiByte
; print two spaces
ld a, 32
call Printc
call Printc
; move to next mem position
inc hl
; decrement counter: if non zero continue loop
dec d
jp nz, monitor_dump_show_bytes_line_loop
call Printc
call Printc
monitor_dump_show_bytes_line_loop: ; counts down from 15 to 0
ld a, d
sub MON_DUMP_BYTES_PER_LINE + 1
jp m, monitor_dump_show_bytes_line_loop_ascii ; jp if
; if position is 8 to 15, print hex value at mem position
ld a, (hl)
; print hex byte
call monitor_printHexByte
; print space
ld a, 32
call Printc
; if position is 4, print a second space (to group nibbles)
ld a, d
cp MON_DUMP_BYTES_PER_LINE / 2 + MON_DUMP_BYTES_PER_LINE + 1
jp nz, no_second_space
; print second space
ld a, 32
call Printc
no_second_space:
; move to next mem position
inc hl
; decrement "nth byte on the line" counter
dec d
jp monitor_dump_show_bytes_line_loop
; if position is 0 to 7, print ascii
monitor_dump_show_bytes_line_loop_ascii:
; is this the first ascii char printed in this line?
ld a, d
cp MON_DUMP_BYTES_PER_LINE
jp nz, no_mempos_decr ; no need to decrement, already done
; do this only once: printing hex values we advanced the counter by 8 positions. Bring it back.
ld bc, MON_DUMP_BYTES_PER_LINE
sbc hl, bc
; print 3 spaces to separate hex from ascii
ld a, 32
call Printc
call Printc
call Printc
no_mempos_decr:
; print ascii
ld a, (hl)
call monitor_printAsciiByte
; print space
ld a, 32
call Printc
; if position is 12 (8+4), print a second space (to group nibbles)
ld a, d
cp MON_DUMP_BYTES_PER_LINE / 2 + 1
jp nz, no_second_space2
; print second space
ld a, 32
call Printc
no_second_space2:
; move to next mem position
inc hl
; decrement counter: if non zero continue loop
dec d
jp nz, monitor_dump_show_bytes_line_loop
; print newline
ld a, 10
call Printc