Instruction manual

030f db 0f in a,(0fh) ;clear INTRQ

0311 c9 ret

0312 ;

0312 ;Strings used in subroutines

0312 .. 00 length_entry_string: defm "Enter length of file to load (decimal): ",0

033b .. 00 dump_entry_string: defm "Enter no. of bytes to dump (decimal): ",0

0362 .. 00 LBA_entry_string: defm "Enter LBA (decimal, 0 to 65535): ",0

0384 08 1b .. 00 erase_char_string: defm 008h,01bh,"[K",000h ;ANSI seq. for BS, erase to end of line.

0389 .. 00 address_entry_msg: defm "Enter 4-digit hex address (use upper-case A through F): ",0

03c2 .. 00 address_error_msg: defm "\r\nError: invalid hex character, try again: ",0

03ee .. 00 data_entry_msg: defm "Enter hex bytes, hit return when finished.\r\n",0

041b .. 00 data_error_msg: defm "Error: invalid hex byte.\r\n",0

0436 .. 00 decimal_error_msg: defm "\r\nError: invalid decimal number, try again: ",0

0463 ;

0463 ;Simple monitor program for CPUville Z80 computer with serial interface.

0463 31 ff db monitor_cold_start: ld sp,ROM_monitor_stack

0466 cd 03 00 call initialize_port

0469 21 dc 05 ld hl,monitor_message

046c cd 18 00 call write_string

046f cd 89 02 monitor_warm_start: call write_newline ;re-enter here to avoid port re-init.

0472 3e 3e ld a,03eh ;cursor symbol

0474 cd 0c 00 call write_char

0477 21 08 db ld hl,buffer

047a cd 4c 00 call get_line ;get monitor input string (command)

047d cd 89 02 call write_newline

0480 cd 84 04 call parse ;parse command, returns with jump add. in HL

0483 e9 jp (hl)

0484 ;

0484 ;Parses (interprets) an input line in buffer for commands as described in parse table.

0484 ;Returns with address of jump to action for the command in HL

0484 01 ba 07 parse: ld bc,parse_table ;bc is pointer to parse_table

0487 0a parse_start: ld a,(bc) ;get pointer to match string from parse table

0488 5f ld e,a

0489 03 inc bc

048a 0a ld a,(bc)

048b 57 ld d,a ;de will is pointer to strings for matching

048c 1a ld a,(de) ;get first char from match string

048d f6 00 or 000h ;zero?

048f ca aa 04 jp z,parser_exit ;yes, exit no_match

0492 21 08 db ld hl,buffer ;no, parse input string