dikdom
commented
2 years ago Hi, in short: no. A bit longer: unfortunately no, but you have all the source files so you can customize it for your needs! :) When I designed this cart my aim was a simple cart that can provide a possibility to load a cart image (most of the carts are to be mapped to A000/BLK5) and keep the costs (bom and time to create) low.
RAM1,2 and 3 are small RAM areas (1kB each) under $1000 - starting at $0400. BLK1, 2 and 3 are 8kB RAM areas starting at $2000, $4000 and $6000. BLK5 is special. It can be selected on this card if there should be RAM or ROM area visible by VIC-20. In case ROM is selected then the last 2 switch selects which 8kB bank shall be mapped there from the ROM IC. In case if RAM is selected then you may have a full 35kB free RAM on you VIC-20 (but no cart).
I'm sure there are possibilities to do what you require just that needs a bit more logic put on that card:
- you need to enable the ROM on BLK5 and BLK3 (instead of the current BLK5-ROM)
- you need to route BLK3 to the ROM as A13 (8kB)
- and of course you need to disable RAM access on BLK3 and BLK5 But this is something I would let YOU to do.. :)
(sorry for the late reply)
VonHirsch
Hello, I'm trying to simulate a game cartridge that has two 8K ROM images - one to load at $6000, and another into $A000. Would this be possible using the jumpers on this board?
I'm not sure on the addresses of RAM1, RAM2, RAM3 and BLK1, BLK2, BLK3 and BLK5 memory areas. Do they correspond to the ones below? Which is $6000 and which $A000?
Thanks for this project!
$0000 System RAM (1K) $0400 Empty space for 3K memory expansion $1000 BASIC RAM (3.5K) $1E00 Screen matrix (0.5K) $2000 Empty space for first block of 8K memory expansion $4000 Empty space for second block of 8K memory expansion $6000 Empty space for third block of 8K memory expansion $8000 Character ROM (4K) $9000 I/O space for VIC chip, VIAs etc (4K space of which only parts are used) $A000 RAM/ROM cartridge space, 8K $C000 BASIC ROM (8K) $E000 KERNAL ROM (8K)