Commodore VIC-20 Diagnostic Cartridge & Test Harness Set - USA seller For Sale

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Commodore VIC-20 Diagnostic Cartridge & Test Harness Set - USA seller:
$39.99
CommodoreVIC-20 Diagnostic Cartridge complete withTest Harness Set.
NEW from AnyRetro!Everything you need to quickly and completely test your beloved Commodore VIC-20.
In addition to the Diagnostic Test Cartridge that completely tests the inner workings of the computer, this set also includes all the necessary dongles to test the external ports:
- Keyboard
- Serial
- Joystick controller
- User Port
- Cassette Port
Multiple diagnostic tests per component include:
- ZERO PAGE
- STACK
- INTERNAL RAM
- EXTERNAL RAM(If present)
- SCREEN RAM
- CHARROM
- BASIC ROM
- KERNAL ROM(S), INCL PAL/NTSC AND JiffyDOS
- VIC CHIP SPECIFIC TESTS
- COLOR RAM
- CASSETTE PORT
- USER PORT
- KEYBOARD MATRIX
- CONTROL PORT
- SERIAL IEC FLOPPY PORT
- VIA1
- VIA2
- IRQ/NMI
- SOUND
The advanced memory testing algorithms go deep to find RAM faults:
- March C- — w0; r0,w1 up; r1,w0 up; r0,w1 down; r1,w0 down; r0. Catches stuck bits, transition faults, and address-decoder faults.
- Solid patterns — $00, $FF, $55, $AA, each written then read back.
- Address uniqueness — low byte of the address stored in each cell, then the high byte. Catches aliased or shorted address lines.
- Walking ones — $01, $02, … $80 written and read at every address. Catches stuck bits and bit coupling.
What's in the box
- VIC-20 Diagnostic Cartridge: Custom circuit board with a reset button on top so you can restart the tests without switching off.
- Cassette port loopback dongle
- User port loopback dongle
- Keyboard loopback dongle(fits the keyboard connector on the motherboard)
- Control port loopback dongle
- Serial port loopback dongle
Compatibility
- Works with PAL and NTSC VIC-20s and detects which one you have.
- Works with original KERNALs and JiffyDOS 6.01 (PAL and NTSC).
- Works on a stock, unexpanded machine. Tests 3K and 8K expansion RAM if you have it fitted.
- No disk drive, tape deck or software needed. Everything runs from the cartridge.
How to use it
- Switch the VIC-20 off.
- Plug the cartridge into the expansion port, and fit the loopback plugs to the ports you want to test.
- Switch on. The tests start straight away.
- Watch the screen. After each full pass it pauses for a couple of seconds and starts again. Leave it running as long as you like to soak-test the machine.
- Press the reset button on the cartridge to start over.
Made in the USA. Fully compatible with all Commodore VIC-20 models, including PAL & NTSC versions.
Elevate your gaming and computing experience today!
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