PCjs Machines

Home of the original IBM PC emulator for browsers.


PCx86 TestMonitor

A few PCjs machines, such as the one below, have enabled TestMonitor support, allowing you to use one of the machine’s serial ports (usually COM2) to control and issue commands to the machine.

After the machine finishes booting to a DOS prompt, type the DOS command CTTY COM2, and then you can interact with the machine via the TestMonitor window.

Typing Ctrl-T in that window toggles it between “terminal mode” and “prompt mode”. After the initial CTTY command, the TestMonitor should detect the DOS prompt and enter “dos mode”, at which point you can type the command debug to enter “debug mode”, where a number of debug macros are available to you, such as:

To see all the command modes, and the macros available in each mode, see tests.json.

There is also a TestMonitor Utility that can be used to control a physical PC from the command-line. When using a physical PC, the INT14.ASM Terminate-and-Stay-Resident (TSR) utility should be installed, to minimize the risk of dropped characters when using the DOS “CTTY” command.

[PCjs Machine "ibm5170"]

Waiting for machine "ibm5170" to load....

Directory of PCx86 TestMonitor

 Volume in drive A is INT14
 Directory of A:\

DOWNLOAD ASM     10032   3-22-20  10:57p
DOWNLOAD COM      1826   3-08-20  12:38a
FAKECTTY ASM      2796   3-08-20  12:38a
FAKECTTY COM       307   3-08-20  12:38a
INT14    ASM     12480   3-08-20  12:38a
INT14    COM      2335   3-08-20  12:38a
MK       BAT       219   3-08-20  12:38a
        7 file(s)      29995 bytes
                      128512 bytes free