This mini forum is intended to provide a simple means of discussion about the RCA Cosmac VIP computer. If you want to share your own experience or memories, or add relevant information about this system: post a message!

The Cosmac VIP was our first computer and my brother and I spent many hours programming it and having fun. Living in Australia, my Dad had it shipped from the US (via my Uncle) and we assembled one weekend.



My brother learned the assembly language and he hacked the video subroutines and created some pretty interesting effects. I am sure it was not too good for the monitor, but one effect was to get the top of the display to fold back in itself (at least that is what it looked like). The he made a terrain type routine that looked like the ground curving onto the screen from the top and disappearing off the bottom.



We added RAM to the board, we had one of our friends burn the CHIP8 language into a ROM and also had the ROM dual boot into two different load states (I think one had the CHIP8 loaded and the other didn’t). We got hold of the ASCII keyboard but never really did anything with it, it was a pretty cool keyboard and used a membrane rather than keys. Very hard to use as there was no tactile feedback at all.



I used to take the Cosmac and a monitor to school and we would play it during recess. One of the games I wrote was a car racing game and to work around my limited knowledge of sprite collision detection I would draw one frame with the cars on it and test for collision, then draw another frame with the cars and scenery which did not detect for collision. As you can imagine, the scenery frame flickered quite a bit, but overall the game went pretty well and all my friends were pretty impressed.

One of the CPU''s I''m very fond of is the CDP1802 by RCA. I had bought this RCA Integrated Circuits data book (I *loved* to read this kind of books) and there was that IC that at first I didn''t understand what it was doing (most of the others were from the TTL 74xx series), until it dawned on me that this was an entire computer in a single IC. One of the landmark events of my life...

I too imported a Cosmac kit from the US (to NZ at that time) in the early 70s, and built it. Great fun programming this thing in hex code !

I designed vehicle traffic counters using the 1802 back in the late 70''s. I''m now trying to find any Cosmac kits or evaluation boards. Please $ me a line at md @ md46 . com if you have news of any 1802 stuff. Mike

This probably doesn't qualify as useful info, but it's a bit of nostalgia for me. This is one of the first computers I actually saw in person and played around with. My father was in the process of opening a video/computer store called Computavid. His friend made a "coming soon" advertisement on this computer and he played it on a TV in the window of the store. This was back in 1980-81 and I was only 12 at the time. I found it to be absolutely amazing and it sparked my interest in computers. I wanted a computer like this, but my father ended up buying me a TRS-80 Model I system. Later when he began selling Commodore 64 computers in his store, I got one for Christmas. I still have it.

First, I would ask a question about the CDP 1802 microprocessor : What's the meaning of the instruction which is writen in hexadecimal (68H)?
- Is there a software to simulate the work of the CDP 1802 microprocessor during the execution of it's 91 instructions?

Thank you very much