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About paulrobson

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    Space Invader
  • Birthday 09/19/1963

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    Norfolk, England

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  1. There's a lot of machines this could be. There is a sequence of them starting with System00 (TTL CPU) various FREDs (1801 CPU) Cosmac ELF/VIP (1802 CPU). The 1801 is a 1802 without the long branch/skip, most of the shift rotates and load without advance. There are also different version of Chip-8 - at least three, the one that is well known that is part of the VIP, The Studio 2 version and the Fred version which is called FEL-1. Joyce W seems to have been programming all of them. They are all different ; though FEL-1 is much closer to Chip 8 graphically. FRED 2 (the naming is a bit vague as to what is what) was produced in small numbers (about 20) to demonstrate to potential buyers. To confuse matters furthers, the FRED papers I acquired from Hagley also have a design for a Cosmac Coin-Operated machine (1801 based) which appears to have been constructed at some point but got no further. It is interesting how different things could have been if different management decisions had been made in respect of the 180x stuff. This stuff predates Space Invaders.
  2. I forgot that Flip wrote a test program which is on the multicart which includes a RAM test, did you try that ? The cart port is fairly chunky, should be fairly reliable ?
  3. I can't see why your console would behave like that. Every reset/power up should be a fresh start. There may be some bugs in the games but not something that obvious. So if you reset Space Invaders it should work again even if there is a bug. Most of the other games (all ?) use the built in Chip-8 type language which uses memory in a very specific way, whereas my games use it in different ways. Maybe a stuck bit in the data RAM memory or something ?
  4. Flappy bird would be fairly easy but I'd do it differently. Invaders would be more appropriate. Invaders can't move the invaders invididually, the 1802 just can't cope, so what it does is remove all the bullets, scroll the whole screen left, right or down as far as the bases, and then draw the bullets back again. Flappy could work the same way ; remove the bird, scroll the whole screen left, draw the bird back, check for collision, draw in the right hand wall and loop.
  5. Okay, the github version of Invaders now has no LBanything LSanything or NOP. I don't think there are any other three cycle 1802 instructions. I've played it a bit and it seems to work fine. You might want to test it but I can't see any reason it should be problematic, it works okay in emulation. I wrote that sixteen years ago ... makes me feel very old. Interesting coding, I appear to have written it as one long bash ... not very modular ... and just used long branches to work round the paging .... still those three were about the first 1802 code I wrote. I notice Combat and Hockey have had some not all of the LBRs fixed. Are the glitches if any in these barely noticeable ? If so, I will just leave them alone if they work okay, so you can get your carts out.
  6. I've sent you an invite to push to the repo - if you want to update it or send me your changes via email ([email protected]), then I can work on Invaders.
  7. Okay, I have set up a repository at https://github.com/paulscottrobson/studio2-games. The three problematic games are the old ones, Combat, Hockey and Invaders which were written before I knew about the 3-cycles issue. I probably won't have time tomorrow but should get it done over the weekend - hopefully !
  8. I will try and get it done in the next couple of days. I'll let you know.
  9. Hi. Thanks for the offer, but I haven't got any way of running it. What's the timescale for sending these out ? I can have a crack at upgrading Invaders (I've obviously learnt for the new ones !) Paul Robson
  10. Question : if I write any more Rcas2 games, to make them compatible with this what memory can I use, beyond the obvious (400-7ff) ? Is it just c00-Fff ?
  11. I didn't know that, I must try it out. My 2711 project was actually running on a genuine CP1610 emulator but I rewrote the whole thing, It was actually running an RISC VM on top of the CP1610 and the game cartridge run on that. I worked the game out from the box pics and the instructions and I suspect it's pretty accurate The AY-3-8800 is so bad a design that it's instant-sacking. Given the expense of producing the chips. It's horribly limited in ways you can't begin to believe until you understand the datasheet. If it wasn't for the fact that it was in a databook with a bunch of other GI chips I'd have assumed it was a wind up. The design of the 2711 is also horribly botched. Externally and internally. It throws away a lot of the advantages of the 1610. I'm quite surprised the carts were dumped. Unisonics are incredibly rare.
  12. The original : http://www.robsons.org.uk/archive/www.classicgaming.com/studio2/cart.htm
  13. I noticed this old post while trying to find something. I've got this working - it was an outgrowth of my VIP project - basically the same thing with a different keyboard and memory map Though it doesn't emulate the RCA2 interpreter, in emulates the 1802, and generates the display at the same time, which says something about how slow the Studio 2 is It's an Uno or other 328 based Arduino (the Leonardo's don't work), a couple of resistors, a piezo buzzer and a pair of 3x4 keypads - the video is a heavily modified version of TVout I'll dig it out and upload it.
  14. Update to Studio 2 homebrew - probably the last for a while - Berzerk. http://www.robsons.org.uk/homebrew.zip Though I will update them to have porting notes in case anyone wants to port them to Elf, Cosmac VIP etc. which is not difficult.
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