VIC Down Under

[DrVeryEvil]

I'm sure everyone has seen something like this, but this one is my custom build of my own design. What's different about this one, you ask? This one has RAM tucked everywhere. Banked under the Kernal, Basic, and Character ROMs. There are two 4K banks under the character ROM. Of course it has the internal 8K in BLK0, making it available to the 6560, as is the RAM under the character rom. I have 4 different versions of the operating system programmed into a flash ROM, including stock boot with all blocks of memory populated as well as one that boots up with the screen matrix moved to $0400, like shown below. I've removed the voltage regulator circuit with a modern buck converter that can handle 5 amps.

If there's any interest in building one of these Xilinx based memory upgrades, I'd be happy to make the schematic from the Xilinx ISE 14.7 Application along with the file to program your CPLD. This requires a plain Jane XC9536, not an XL. I can program the CPLD for a fee of $50 USD. This will not include the internal 8K at BNK0. I just use point to point wiring on my circuits. With so many different VIC 20 board versions, I cannot send instructions for installation. I can include pix and pointers of my VIC. The schematic shows connections that are intuitively named. This is an advanced project and I make no guarantee that yours will work.

I have converted the "Fast Assembler" program from the old Computes' Gazzette Magazine to run on this VIC, which makes assembly language much easier

Cheers

[Noizer]

Very interesting.
So many cables criss-cross, it is surprising that it works well at all. For which applications do you use this thing anyway? Do you have a copy of the „Fast assembler“ in its original state to share?

[DrVeryEvil]

Point to point wiring can look messy. All the signals required come from all over the VIC20 board. I try to find pass throughs when possible. It has a register mapped at $9200 that acts just like on the C64, $0001. The Fast Assembler can be found in the January 1986 issue of Computes' Gazzette. Here's the link that also has the companion disk available. I use this computer just for experimenting with. With two 4K banks of RAM at $8000, I can have two bitmaps and switch between the two easily by changing a bit in the register. Yes the VIC chip has access to the memory at $8000.

https://archive.org/details/antic-magazine-disks