##       ##    ##         ##     ##  #######  ##    ## #### ########  #######  ########  
##       ##   ##          ###   ### ##     ## ###   ##  ##     ##    ##     ## ##     ## 
##       ##  ##           #### #### ##     ## ####  ##  ##     ##    ##     ## ##     ## 
##       #####    ####### ## ### ## ##     ## ## ## ##  ##     ##    ##     ## ########  
##       ##  ##           ##     ## ##     ## ##  ####  ##     ##    ##     ## ##   ##   
##       ##   ##          ##     ## ##     ## ##   ###  ##     ##    ##     ## ##    ##  
######## ##    ##         ##     ##  #######  ##    ## ####    ##     #######  ##     ##

Resident Monitor for IBM PC/XT 5160

Tested on:

• qemu (i386) -fda (st returns 0x20 - Controller failure)
• emu8086 (100% works)
• PCjs (100% works)
• DosBOX (100% works)

Commands

[] - optional param, {} - required param

• ?[XXXX] show memory content.
• >[XXXX] add [XXXX] to address pointer (One if [XXXX] not provided.
• <[XXXX] subtract [XXXX] from address pointer (One if [XXXX] not provided).
• ld{XXXX} load sector {XXXX} from disk to current address.
• st{XXXX} store 512 bytes from current address on sector XXXX} of disk.
• .{string} store {string} at current address (Null-terminated). Accepts *n as 13,10 and ** as *.
• #[XXXX]start executing code from [XXXX] (Current address if [XXXX] not provided).
• ={XXXX} set address pointer to {XXXX}.
• {XX...} store {XX...} at current position.

How to make image from source

Linux

nasm ldr.asm -f bin -o ldr.bin
nasm mon.asm -f bin -o mon.bin
cat ldr.bin mon.bin > mon.img

Windows / MS/DR/Free/PC DOS

nasm ldr.asm -f bin -o ldr.bin
nasm mon.asm -f bin -o mon.bin
type ldr.bin mon.bin > mon.img