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WIP Zero command in monitor

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Daniele Verducci (ZenPenguin) 2020-12-26 12:39:18 +01:00
parent a55741f010
commit 4dfd5fb61a
1 changed files with 32 additions and 1 deletions
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33
assembly/bios/monitor.asm
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@ -17,11 +17,12 @@ MON_WELCOME: DB 10,"PAT80 MEMORY MONITOR 0.2",10,0
MON_COMMAND_HELP: DB "HELP",0 ; null terminated strings
MON_COMMAND_DUMP: DB "DUMP",0
MON_COMMAND_SET: DB "SET",0
MON_COMMAND_ZERO: DB "ZERO",0
MON_COMMAND_LOAD: DB "LOAD",0
MON_COMMAND_RUN: DB "RUN",0
MON_COMMAND_ADB: DB "ADB",0
MON_ARG_HEX: DB " 0x",0
MON_HELP: DB 10,"Available commands:\nHELP prints this message\nDUMP [ADDR] shows memory content\nSET [ADDR] sets memory content\nLOAD\nRUN [ADDR] executes code starting from ADDR\nADB starts Assembly Deploy Bridge",0
MON_HELP: DB 10,"Available commands:\nHELP prints this message\nDUMP [ADDR] shows memory content\nSET [ADDR] sets memory content\nZERO [ADDR] [ADDR] sets all bytes to 0 in the specified range\nLOAD\nRUN [ADDR] executes code starting from ADDR\nADB starts Assembly Deploy Bridge",0
MON_MSG_ADB: DB 10,"Waiting for data.",0
MON_ERR_SYNTAX: DB " Syntax error",0
;MON_ADB_TIMEOUT: EQU 0xFF // Number of cycles after an ADB binary transfer is considered completed
@ -53,6 +54,9 @@ Monitor_main:
ld hl, MON_COMMAND_SET
cp (hl)
jp z, monitor_set
ld hl, MON_COMMAND_ZERO
cp (hl)
jp z, monitor_zero
ld hl, MON_COMMAND_LOAD
cp (hl)
jp z, monitor_load
@ -223,6 +227,33 @@ monitor_set:
inc hl ; next memory position
jp monitor_set_byte_loop
; Asks user for a memory range and sets all bytes to zero in that range in memory
; @uses a, b, c, h, l
monitor_zero: ; TODO: bugged, doesn't exit cycle
ld bc, MON_COMMAND_ZERO + 1 ; autocomplete command
call Print
; Now read the starting memory address
call monitor_arg_2byte ; returns the read bytes in hl
; starting addr in bc
ld b, h
ld c, l
call monitor_arg_2byte ; ending addr in hl
; Start looping memory addresses (from last to first)
monitor_zero_loop:
ld (hl), 0 ; set byte to 0 in memory
dec hl ; next byte
; check if we reached start addr (one byte at time)
ld a, b
cp h
jp nz, monitor_zero_loop ; first byte is different, continue loop
; first byte is equal, check second one
ld a, c
cp l
jp nz, monitor_zero_loop ; second byte is different, continue loop
; reached destination addr: zero the last byte and return
ld (hl), 0 ; set byte to 0 in memory
ret
monitor_load:
ld bc, MON_COMMAND_LOAD + 1 ; autocomplete command
call Print