Debug Ü ßßßßßß Starts the Debug program, which you can use to test and debug executable files. Syntax: DEBUG [[[d:]path]file] d:path\file The name of a debugger script file. The debugger should allow the user to specify a file name to load by the script file. Debug commands A Assembles the instructions at a particular address C Compares two memory ranges D Displays the contents of the memory E Enters new or modifies old memory contents F Fills a range in memory G Executes a program in memory H Adds and subtracts two hex values I Inputs and displays a byte from a port L Loads disk data into memory M Copies a range of memory values N Names a file to load or create O Outputs a byte to a port P Proceeds with execution to the next memory instruction Q Quits Debug R Displays (and changes) contents of registers and flags S Searches for characters T Traces execution of memory code U Unassembles hex bytes into assembler instructions W Writes memory data to disk XA Allocates expanded memory XD De-allocaes expanded memory XM Maps logical pages onto physical ones XS Displays expanded memory status Example: This program will read any keystroke and make it easy for you to test whether or not that key was typed during a batch file's execution: Create the file keyscan.scr A 100 MOV AH,0 INT 16 MOV AL,AH MOV AH,4C INT 21 RCX A N KEYSCAN.COM W Q Then type at the command prompt: C:\>debug < keyscan.scr