spookt

00011593 bought from Amazon UK

Sorry to hear that.

Congratulations everyone! Some great projects as always. Hopefully I’m already on the waiting list for the DecentXL. Can’t wait to get my fingers on one!

OK - short story - it’s all working fine now 🤣 The long story is about a day’s work. I decided to take the board back to stock as there were some decidedly odd things happening. In the process I ended up with a non booting board, brown screen. Checked all the custom chips, mmu, OS ROM etc in a spare board - all good. Checked clocks via scope - all present. Could see activity on address lines. The DRAMs on the board were already socketed so I pulled them to test in my RCT pro. And there was the problem. 50% of the RAM was borderline (testing OK on 1 pass then bad on another) or just bad! Turns out a fair bit few of my spares test out as bad too 🙁 Well they have been on the shelf a while! Finally found enough good RAM and put the board back together as stock. All good, booting up to READY. From there I added one upgrade back at a time testing as I went. PokeyMax went in last. System seemed stable. Definitely not seeing stalling SIO I had previously. Tested a couple of stereo games and demos (including Numen) at standard and high speed SIO and all looked good. Decided to push my luck and reflash the PokeyMax to Stereo + Covox (from Quad Pokey). Flashed the core and moved the address line and all good. Tested with a couple of Covox demos. it’s taken a bit of work but I’m finally there. 800XL with U1Mb, VBXE, Side2 and PokeyMax (Stero plus Covox). This is pretty much my ‘dream’ machine as far as daily use goes and I’m already enjoying it. Thanks everyone for the support and suggestions when things weren’t working and thanks to the folks who continue to create amazing upgrades and software for these machines.

I spent a little time this evening scoping the serial IO pins on the PokeyMax in both machines and I struggled to see a difference. SIO just randomly stalls in the bad machine and can often be restarted by hitting break. In desperation I decided to revert the board to stock except the PokeyMax. I removed the VBXE first and reinstated the legacy system clock as I had suspicions that the odd behaviour was a timing issue but there was no change. Next I removed the U1Mb. This seemed to make things a little better, but I was still seeing stalling SIO almost all the time. Clutching at straws I swapped the CPU from the other test machine in. And voila! SIO problems are (almost*) history. So I need to put the other CPU into the stock test machine and see if SIO fails there. I’ve now put the U1Mb back in and all seems well. Just about to reinstall VBXE. * I say almost because I’ve seen one or two stalls with the new CPU, but it’s a massive improvement. I’ll do more testing over the weekend.

Yep I have an oscilloscope. Directions on the kind of things to check would be gratefully received.

I finally had some time to connect up the address lines. Also identified that this is the Quad Auto version. It has core 127M04QA which looks like its the latest? I tried 3 spare PIAs but without much improvement. Still bad SIO which feels very much like a timing issue (hitting break will resume the SIO operation and things eventually load, which is how I can boot the config program). I have installed it in a spare stock 800XL where it seems to behave normally so there must be something about my main machine it doesn't like. I'm guessing other folks are using PokeyMAX in conjunction with VBXE and U1Mb? Oh and by the way - if and when I get it running is the hardware the same across these devices? Can you flash a different core to get different functionality? (COVOX vs Quad Pokey etc)?

Nope. It has U1mb and VBXE

I’ve lifted the caps and it’s made no difference. Yeah. I’m ignoring the config program for now and just concentrating on getting basic SIO working reliably.

edit: duplicate post

Yes. I was mistaken, apologies. I’ll try lifting them and see if it makes a difference. Not sure why it should when I’ve been successfully running up to the highest speeds with a stock Pokey?

It doesn’t 🤪 However I’ve just dropped it into a stock 800XL board which was already socketed and SIO seems to work fine. Sigh. Why is nothing ever straightforward? I don’t think there’s much point doing the full install in my U1mb machine until I can see good SIO and so I need to understand what the issue with that machine is. it works perfectly fine with a stock Pokey. I can run high speed SIO, Side 2, SpartaDOS and real or virtual floppies, games etc with no issue at all. It my daily driver and has been rock solid. It apparently just doesn’t like PokeyMax!

OK. So I made up a physical floppy with DOS 2.5 and the pokeycfg_1.3_xex file and there's no difference in behaviour. (I've takn everything off the SIO chain except a stock 1050 and put the system into stock mode in the U1Mb BIOS) I'm going to wait for my headers to come in so I can wire things up properly but I'm not particularly hopeful. Can anyone confirm that once the PokeyMax is installed in place of the original chip, before making other connections, the system should behave normally? Eg. should I be able to boot DOS 2.5 from a physical floppy?

This is an 800XL. I thought only the XE line has the SIO filter caps? I'm pretty sure the my FujiNets have the latest firmware but I'll check. As far as the config tool goes I haven't tried to flash the core because of the SIO problems. I'll make up a DOS disk and load the flash from there and see if there are any different results identifying the version. My headers should come in tomorrow so I can wire the thing properly, but I really expected basic SIO to work without that. That's definitely implied in the instructions. EDIT - It might be work clarifying that I can’t boot ANYTHING reliably with the PokeyMax installed from a physical or virtual drive.

Hey Folks I finally got my hands on a PokeyMax V 2 from RetroLemon. I'm waiting on some right angle headers to come in to hook up audio out etc, but obviously couldn't wait to try the thing out. The Pokey in my daily driver 800XL is already socketed so I whipped the Pokey out, replaced the 10uF cap below it so I could lie it down out of the way and dropped in PokeyMax. At this point I was expecting the system to behave as if it had a stock single Pokey. I haven't made any other connections and in fact the installation instructions suggest testing the system for keyboard, SIO etc function at this point. I'm seeing some pretty random SIO behaviour in the system right now. I've tested with two FujiNet devices and a real stock 1050 and I'm getting random timeouts and hangs when booting disks or images. SIO polling noise (the Atari Fart (tm)) etc. I managed to get the config tool to load by mounting it on FujiNet and repeatedly hitting break when the timeouts occur and I get random characters instead of a core version so I guess something weird is going on. Corrupted flash? Do I need to USB Blast the thing? Screen shot of config tool running: EDIT - Machine has U1Mb and VBXE installed too.