exxos's Atari, Amiga & retro forum

great.
would be possible to put TOS somewhere inside TF? Would be cool to take a benefit from faster RAM/ROM access.

Been requesting it for ages ;)

But you don't need ROM on TF to use faster ROM access. In fact I have been talking to TF this week about him adding in a ROM_OE to bypass the GLUE decoding ROM, so we can use TOS206. This is why TF brought one of my ROM boards a couple days ago to work on it.

https://www.exxosforum.co.uk/forum/viewt ... =20#p15841

Okay, well it *sort of works*

So I found out why it was only working if I left the programmer plugged in. There was a stack of noise on my 3v3 line and the programmer was suppressing the noise. So I changed the regulator and 3v3 was nice and clean but it then wouldn't boot at all.

Plugging the test cartridge in I get the blue screen and it hangs on "I6 Testing Bus Error handling". Probing around everything looked normal except IPL2 is low. Probed around without the test cartridge and it was the same. Then while probing I accidentally shorted IPL2 and BERR and it booted! (and IPL2 goes high) - Then when GEM desktop loads and IPL2 goes low and the computer freezes, short it again and IPL2 goes high again and it continues to operate normally. This is repeatable every boot.

I don't have the low level knowledge to have a clue what any of this means. :( I'm hoping that someone with a bit more experience can offer some insight. It's probably worth noting that I'm using KAOS TOS as my ST is too old to support 2 chip TOS.

Any ideas? Thanks. :)

Disregard last post. It turned out to be a bad firmware. Found a better firmware and now it's working a treat. :)

sety wrote: 24 Dec 2018 07:04 Disregard last post. It turned out to be a bad firmware. Found a better firmware and now it's working a treat. :)

:thumbup:

Time for a update though ;)

http://www.exxosforum.co.uk/atari/last/GB6/index.htm

exxos wrote: 24 Dec 2018 10:11 Time for a update though ;)

Thanks Chris. I'll do that in the New Year. :) I found that copy on my Falcon, and it's the only thing I can write floppies with as everything else is packed up to clear space (and power points) for Christmas. I really just needed something that would make the computer do some work to see if my build was reliable. :lol:

A few things I've learned that I'd like to share in case someone else is wanting to do the same thing, while I still remember it;

1) Although not officially supported, building the TF520 was great fun and is a good way to get one's confidence up before taking on the 530.

2) I don't know who FreyaAmiga (GitHub) is but the PCB design files are good. I couldn't get the firmware to work. The firmware on TF's GitHub repo terriblefire-binaries (for the lazy) works.

3) LM2836-3.3 in TO-92 is not a suitable replacement for the reg in the design! (this is the only 3.3 reg available in Australia off the shelf) so if you're in Australia, don't bother! It was as noisy as hell and also expensive ($5.00 each!) I ended up stealing the correct part from an Arduino board.

4) The Xilinx programmers running around on eBay aren't real Xilinx Platform USB programmers, even though they look the same and are licensed. They're Diligent JTAG. They work, but not so seamlessly. In Impact, you have to "software disconnect" the cable to get the options to program/erase/verify/etc. It will reconnect itself for each step. Knowing this will save you hours of tearing your hair out. :)

5) The oscillator is super hard to find. I couldn't even get it in China. I have some on order from the UK (the only place in the world I could find them) which is why I'm still using the ST clock. ;)

Hope this helps someone. :D

The knockoff Xilinx programmers need run once with ISE 10.2. Then they work fine. Otherwise they have the wrong firmware in them. I covered this extensively in my videos.

If picture is with TF520 seems that Atari get more speed gain with it than Amiga.

This is not a requirement, just a opinion and observation.

http://amiga.resource.cx/exp/supra28 see included benchamark. It is 68000 accelerator without any ram, just 16kb data cache.

So Amiga accelerator without ram get huge 4x power boost even with tiny 16kb datacache.