A Breakoutboard For The C64 Expansion Port
I thought, it would be nice to be able to access the expansion port signals, while a cartridge is inserted. This would be quite helpful for debugging a cartrdge with a scope or logic analyzer. Further, it would be nice to be able to disable some of the chip selects, interrupts and control signals, too.
Those are:
● /ROML
● /ROMH
● /IO1
● /IO2
● /IRQ
● /NMI
● /RESET
● /GAME
● /EXROM
● /DMA
The signals are jumpered. Pulling the jumper is disabling them. There is also +5V and GND on this jumper. Theoretically, it would be possible to manipulate the signals with a micro controller/arduino for analyzing a cartridge.
The box connector allows to access all signals on the C64 side. Further, this can serve for breadboarding a cartridge.
Those are:
● /ROML
● /ROMH
● /IO1
● /IO2
● /IRQ
● /NMI
● /RESET
● /GAME
● /EXROM
● /DMA
The signals are jumpered. Pulling the jumper is disabling them. There is also +5V and GND on this jumper. Theoretically, it would be possible to manipulate the signals with a micro controller/arduino for analyzing a cartridge.
The box connector allows to access all signals on the C64 side. Further, this can serve for breadboarding a cartridge.
Cart64out Rev. 0
Cart64out in situ, with standoffs as a mechanical support
Cart64out Rev. 1
Cart64out Rev. 1 assembled