Instruction manual

0175 23 inc hl ;hl now points to next value

0176 22 04 db ld (value_pointer),hl

0179 2a 06 db ld hl,(current_value) ;get back current value

017c 3d decimal_add: dec a ;add loop to increase total value

017d fa 84 01 jp m,decimal_add_done ;end of multiplication

0180 19 add hl,de

0181 c3 7c 01 jp decimal_add

0184 22 06 db decimal_add_done: ld (current_value),hl

0187 c3 50 01 jp decimal_next_char

018a 37 decimal_error: scf

018b c9 ret

018c c3 7c 01 jp decimal_add

018f 01 00 0a 00 64 00 e8 03 10 27 decimal_place_value: defw 1,10,100,1000,10000

0199 ;

0199 ;Memory dump

0199 ;Displays a 256-byte block of memory in 16-byte rows.

0199 ;Called with address of start of block in HL

0199 22 00 db memory_dump: ld (current_location),hl ;store address of block to be displayed

019c 3e 00 ld a,000h

019e 32 03 db ld (byte_count),a ;initialize byte count

01a1 32 02 db ld (line_count),a ;initialize line count

01a4 c3 d9 01 jp dump_new_line

01a7 2a 00 db dump_next_byte: ld hl,(current_location) ;get byte address from storage,

01aa 7e ld a,(hl) ;get byte to be converted to string

01ab 23 inc hl ;increment address and

01ac 22 00 db ld (current_location),hl ;store back

01af 21 08 db ld hl,buffer ;location to store string

01b2 cd 88 00 call byte_to_hex_string ;convert

01b5 21 08 db ld hl,buffer ;display string

01b8 cd 18 00 call write_string

01bb 3a 03 db ld a,(byte_count) ;next byte

01be 3c inc a

01bf ca 09 02 jp z,dump_done ;stop when 256 bytes displayed

01c2 32 03 db ld (byte_count),a ;not finished yet, store

01c5 3a 02 db ld a,(line_count) ;end of line (16 characters)?

01c8 fe 0f cp 00fh ;yes, start new line

01ca ca d9 01 jp z,dump_new_line

01cd 3c inc a ;no, increment line count

01ce 32 02 db ld (line_count),a

01d1 3e 20 ld a,020h ;print space