owen2a03 Posted May 2 Share Posted May 2 Hello!! Been around AtariAge every now and then but just now joining. Couple weeks ago I randomly stumbled upon an Atari 800XL from a facebook seller, in MY city!! It was so random, and I never expected to use an Atari 8-Bit computer, let alone own one, but with the 50usd price I couldn't pass it up. I picked it up THAT NIGHT at the request of the seller and was happy to! Got it home and tried it on, and it didn't quite boot up....but after cutting off the power connector and soldering it to a spare USB power cable, it came to life! Probably shouldn't of bothered with the decades old power brick that's only supplying 5 volts.... It's in great shape, it noticeably hasn't been used since the mid-eighties. I went straight to modding it a bit, as I tend to do. Firstly I gave the video connector a center pin for chroma, as besides from that missing pin, the C64 video pinout is very similar, so I can use the same cable between my two computers. Next, I learned RespeQt and figured out I could connect an FTDI breakout board to the serial port and load programs from my PC, and played around with that I discovered a handful of programs needed more memory than the 64K the box boasted so much about... so I got on that! Directly referencing the Rambo XL, I replicated the PCB with careful wiring... waited for the chips, socketed them and hooked up my homemade Rambo, and after some troubleshooting (missing ONE wire...) I got a big RAM boost! It was a really fun project for me, and it felt nice giving this computer new life, forty years later! I've also decided to grab a PAL ANTIC chip to get PAL programs working properly. With that in mind, I'd love to hear any recommendations on what I should play around with with this computer! And, thanks to the forums for the vast information surrounding Atari hardware which helped me a lot in this project! 6 Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted May 2 Share Posted May 2 (edited) @owen2a03 Welcome to AA and good job on the machine. It's fantastic you got a fully factory socketed 800XL there. A lot don't come socketed, making upgrading and/or troubleshooting a lot more problematic. It's also lucky you got a stock 800XL rather than an 800XLF (externally look the same, but under the hood you have a board with a Freddie chip and no 74LS158's, which means the board isn't Rambo XL compatible). You'll find a hell of a lot of existing topic threads on AA advising newbies on what you can load and do with these amazing machines, so IMHO not worth repeating here. Just search but also go to the pinned newbies topic at the top of the Atari 8 bit computers forum. As you have the homemade Rambo xl, it opens up a lot. (Although you appear to have 278k ram there in the image you posted. I'd expect 256k, with more banks reported. Not sure if there is an issue there, unless I am overlooking something?) Game wise check out the likes of modern Doom and Prince of persia Ports, among 100000s of other games, old and new. (Oh yeah, you heard me right Doom and PoP on the A8 ) Again I could list loads games here, but it's all been done before, and the pinned newbies topic is a great place to start. Apart from anything else it'll link you to huge software repository sites hosted by the likes off Atarimania.com and Atarionline.pl. EDIT: Try Simcheck Edited May 2 by Beeblebrox Quote Link to comment Share on other sites More sharing options...
owen2a03 Posted May 2 Author Share Posted May 2 Thanks!! I did get super lucky with the specific 8-bit I got, I think out of all of them I'd want this one, on top of it being all socketed (I do quite like the 130XE design and subsequently the XEGS) I'll definitely move onto the software side of the forum's threads and see what I can find! Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted May 2 Share Posted May 2 That system test tool looks like it may have been completely confused by the RAMBO banking (where 64K of the extended RAM comprises the base RAM). Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted May 2 Share Posted May 2 (edited) 24 minutes ago, flashjazzcat said: That system test tool looks like it may have been completely confused by the RAMBO banking (where 64K of the extended RAM comprises the base RAM). Wonder what it would look like with Simcheck(?) Guess we'll see. IIRC normally it's 16 banks of ram, not 13. Edited May 2 by Beeblebrox Quote Link to comment Share on other sites More sharing options...
flashjazzcat Posted May 2 Share Posted May 2 Yes. Powers of two certainly tend to be the common quantifier. 1 Quote Link to comment Share on other sites More sharing options...
TZJB Posted May 2 Share Posted May 2 9 hours ago, owen2a03 said: Hello!! Been around AtariAge every now and then but just now joining. Couple weeks ago I randomly stumbled upon an Atari 800XL from a facebook seller, in MY city!! It was so random, and I never expected to use an Atari 8-Bit computer, let alone own one, but with the 50usd price I couldn't pass it up. I picked it up THAT NIGHT at the request of the seller and was happy to! Got it home and tried it on, and it didn't quite boot up....but after cutting off the power connector and soldering it to a spare USB power cable, it came to life! Probably shouldn't of bothered with the decades old power brick that's only supplying 5 volts.... It's in great shape, it noticeably hasn't been used since the mid-eighties. I went straight to modding it a bit, as I tend to do. Firstly I gave the video connector a center pin for chroma, as besides from that missing pin, the C64 video pinout is very similar, so I can use the same cable between my two computers. Next, I learned RespeQt and figured out I could connect an FTDI breakout board to the serial port and load programs from my PC, and played around with that I discovered a handful of programs needed more memory than the 64K the box boasted so much about... so I got on that! Directly referencing the Rambo XL, I replicated the PCB with careful wiring... waited for the chips, socketed them and hooked up my homemade Rambo, and after some troubleshooting (missing ONE wire...) I got a big RAM boost! It was a really fun project for me, and it felt nice giving this computer new life, forty years later! I've also decided to grab a PAL ANTIC chip to get PAL programs working properly. With that in mind, I'd love to hear any recommendations on what I should play around with with this computer! And, thanks to the forums for the vast information surrounding Atari hardware which helped me a lot in this project! Welcome to Atari Age. You have a very nice clean 800XL with very little internal rust and a very reasonable home made Rambo XL. You could have saved some space and money by leaving the two redundant chips from your build of the RamboXL. You have a newer (than the 1200XL) version of ANTIC so you only needed two extra logic chips for the decoder. However your RAM upgrade should appear as 12 extra 16KB banks = 192KB, so try SIMCHECK and SIMTEST, the latest versions being in the link @Beeblebrox provided. I am glad that you finally found an Atari 800XL to take home and play with! 😁 Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted May 2 Share Posted May 2 (edited) 28 minutes ago, TZJB said: Welcome to Atari Age. You have a very nice clean 800XL with very little internal rust and a very reasonable home made Rambo XL. You could have saved some space and money by leaving the two redundant chips from your build of the RamboXL. You have a newer (than the 1200XL) version of ANTIC so you only needed two extra logic chips for the decoder. However your RAM upgrade should appear as 12 extra 16KB banks = 192KB, so try SIMCHECK and SIMTEST, the latest versions being in the link @Beeblebrox provided. I am glad that you finally found an Atari 800XL to take home and play with! 😁 Check this out also (where I realise you have already created your own Rambo XL (and enjoyed doing it), plus of course this is sold in the UK.) Still: https://www.ebay.co.uk/itm/266673794264 Edited May 2 by Beeblebrox 2 Quote Link to comment Share on other sites More sharing options...
TZJB Posted May 2 Share Posted May 2 32 minutes ago, Beeblebrox said: Check this out also (where I realise you have already created your own Rambo XL (and enjoyed doing it), plus of course this is sold in the UK.) Still: https://www.ebay.co.uk/itm/266673794264 Thanks but you know that there are just too many chips on that board for me 🙂. Here is a diagram showing what's what:- 1 Quote Link to comment Share on other sites More sharing options...
Overange Posted May 2 Share Posted May 2 30 minutes ago, TZJB said: Thanks but you know that there are just too many chips on that board for me 🙂. Here is a diagram showing what's what:- The newer version is now built with only three ICs fitted. 1 Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted May 2 Share Posted May 2 7 minutes ago, Overange said: The newer version is now built with only three ICs fitted. upload a pic if ya have one Quote Link to comment Share on other sites More sharing options...
TZJB Posted May 2 Share Posted May 2 1 hour ago, Overange said: The newer version is now built with only three ICs fitted. Now that's what I'm talking about! I can test one if you like? Getting technical, does anyone know why we don't need pullup resistors on the PIA bank select outputs? Quote Link to comment Share on other sites More sharing options...
owen2a03 Posted May 2 Author Share Posted May 2 Thanks for pointing that out, 13 banks did seem a bit strange, but the few programs I tried out didn't seem to have any issues 🤷♂️ I loaded SimCheck.. this seems more about right, wasn't sure if there was something up with my Rambo board. I was just using Shortest to confirm the CPU was recognizing the extended RAM as it wasn't at first Thanks for the advice! 1 Quote Link to comment Share on other sites More sharing options...
Beeblebrox Posted May 2 Share Posted May 2 (edited) 28 minutes ago, TZJB said: Now that's what I'm talking about! I can test one if you like? They've been in circulation for a while and work a treat. Edited May 2 by Beeblebrox Quote Link to comment Share on other sites More sharing options...
TZJB Posted May 2 Share Posted May 2 30 minutes ago, owen2a03 said: Thanks for pointing that out, 13 banks did seem a bit strange, but the few programs I tried out didn't seem to have any issues 🤷♂️ I loaded SimCheck.. this seems more about right, wasn't sure if there was something up with my Rambo board. I was just using Shortest to confirm the CPU was recognizing the extended RAM as it wasn't at first Thanks for the advice! There seems to be a problem with your Rambo XL. It shows that PB7 is in use and it shouldn't be. Could you show us a better picture of your PIA please? This is my Simcheck from a while ago:- Quote Link to comment Share on other sites More sharing options...
Overange Posted May 2 Share Posted May 2 16 minutes ago, Beeblebrox said: They've been in circulation for a while and work a treat. Yeah where is your installation photos I have redesigned the PCB to a three chippy version, but as I had loads of bare 5 chippy boards, its best to use them up first. I will upload one when I get chance. 1 1 Quote Link to comment Share on other sites More sharing options...
owen2a03 Posted May 3 Author Share Posted May 3 Got home and opened up the computer, here's the PIA, I cant immediately tell if the wiring is wrong or anything, take a look Quote Link to comment Share on other sites More sharing options...
ClausB Posted May 3 Share Posted May 3 (edited) The PIA wiring is correct. Maybe the PB7 indication is normal for your version of the SimCheck software. PB7 is, after all, involved in bank switching high RAM and ROM. Edited May 3 by ClausB 1 Quote Link to comment Share on other sites More sharing options...
owen2a03 Posted May 3 Author Share Posted May 3 Im loading this program via Picodos that RespeQt came with, my thought was maybe something to do with the computer loading that into memory as well as SimCheck... just a theory, but so far everything seems to be going smoothly anyways! Quote Link to comment Share on other sites More sharing options...
Panther Posted May 3 Share Posted May 3 10 hours ago, TZJB said: There seems to be a problem with your Rambo XL. It shows that PB7 is in use and it shouldn't be. 1 hour ago, ClausB said: The PIA wiring is correct. Maybe the PB7 indication is normal for your version of the SimCheck software. PB7 is, after all, involved in bank switching high RAM and ROM. Ugh! Why has nobody noticed this bug that crept into the most recent couple versions of SimCheck? It looks like bit 7 is always showing it's being used no matter what the memory configuration, as long as there are any extended memory banks. I'd been meaning to release 1.7 at some point anyway, but have been sidetracked. I'll look into it. 2 Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted May 3 Share Posted May 3 12 minutes ago, Panther said: Ugh! Why has nobody noticed this bug that crept into the most recent couple versions of SimCheck? It looks like bit 7 is always showing it's being used no matter what the memory configuration, as long as there are any extended memory banks. I'd been meaning to release 1.7 at some point anyway, but have been sidetracked. I'll look into it. I never mentioned it because I always thought it just meant that the Self Test Bank was available. Quote Link to comment Share on other sites More sharing options...
Panther Posted May 3 Share Posted May 3 30 minutes ago, reifsnyderb said: I never mentioned it because I always thought it just meant that the Self Test Bank was available. It should just be reporting which bits control the actual bank numbers, not even bit 4 is reported. Quote Link to comment Share on other sites More sharing options...
owen2a03 Posted May 3 Author Share Posted May 3 Didnt expect an issue with the program, assuming Im all good to not touch the RAM till I discover any issues? Still been working great, downloaded more stuff to try out Quote Link to comment Share on other sites More sharing options...
reifsnyderb Posted May 3 Share Posted May 3 13 minutes ago, Panther said: It should just be reporting which bits control the actual bank numbers, not even bit 4 is reported. Well, technically speaking, bit 7 does control a bank. It's just not RAM. I do get what you are aiming for, though. Either way, your utilities work great and I've been using them to test out a lot of boards. 🙂 1 Quote Link to comment Share on other sites More sharing options...
Panther Posted May 3 Share Posted May 3 27 minutes ago, reifsnyderb said: Well, technically speaking, bit 7 does control a bank. It's just not RAM. I do get what you are aiming for, though. Either way, your utilities work great and I've been using them to test out a lot of boards. 🙂 Glad they mostly work! Apparently the bug crept in when I was fixing the issue of RAMBO 256K having one of its banks underlying the OS. I fixed this, but made a mistake that allowed bit 7 to get set during this somehow. It will be corrected in version 1.7, which otherwise just has some code cleanup improvements resulting in slightly lower memory usage (which explains why I didn't bother to release it yet). 4 1 Quote Link to comment Share on other sites More sharing options...
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