MASTERFACE 2B: Features and Controls

MASTERFACE 2B

I remember the days when I had to wait a good five minutes for a tape game to load. Back then I read about a turbo add-on that doubled the loading speed. Some time later, MASTERFACE 1 appeared. It had a built-in turbo, as well as the MAD monitor and SAVER in its own EPROM memory. SAVER was a program that copied the entire RAM, including the registers. Once loaded, a program saved this way resumed from where it had been interrupted.

Not long after, a real marvel came along: MASTERFACE 2. I must not forget the author, a certain ANDY SOFT, who built it. The device plugs into the edge connector (the interface has a pass-through connector).

What does it offer?

At the top of the case there is a switch that triggers an NMI interrupt. This freezes the program currently running; stripes on the border indicate that it has been frozen. MASTERFACE 2 is now ready to use.

Key functions

• 1 — Return to the program. You can use this as a PAUSE in games.
• 2 — Go to BASIC without clearing RAM. Only BASIC itself will be cleared.
• 3 — Print the current screen on a printer.
• 4 — SAVER, the memory “recorder” mentioned above, which saves memory to tape. For example, if you have got far in a game, you can save its current state and continue at any time.
• 5 — Use the NMI interrupt for your own purposes. For advanced users only.
• 8 — POKERAMA, a program that searches for the memory cell containing, for example, the number of lives or bullets.

POKERAMA commands:

• U — Search for a sequence
• S — Search for an address
• N — Next address found
• X — Return

Here is how to use it: in a game, we have three lives. Interrupt the game, press 8, then U, enter the sequence 03, 02, 01, press ENTER, and then X. Lose one life, interrupt the game again and press S. Write down the address if one appears, then press X. To get more lives, use the monitor to enter the appropriate POKEs.

• 9 — TURBO CAC, a tape-to-tape copier that can copy at three speeds: Low (normal), High (for storing data) and Turbo (twice as fast).
• 0 — MAD memory monitor. It can be used to view and modify memory, and even to write machine code. All numbers are hexadecimal.

MAD monitor keys

• 1 — Registers. After pressing it, press 9 to see their current values. To change a register, select it with the cursor keys and press I. Then enter the value in hexadecimal. Press X to leave the register screen.
• Q — Return to the running program.
• W — Set a breakpoint. When the program reaches it, an NMI interrupt is triggered automatically.
• R — Reset the system.
• P — POKE address,value.
• S — Save a memory block without a header. Enter the address and length of the block to save.
• D — Convert a decimal number to hexadecimal.
• G — Search for a sequence of values (N finds the next matching sequence).
• H — Convert a hexadecimal number to decimal.
• J — Load a block from tape. Enter the address and length.
• L — List memory as ASCII codes.
• M — Set the starting address for the listing.

As you can see, this add-on has quite a lot to offer. Its only drawback is that it does not work with a disk drive.

PYZA