TF project.

TF520 - 68020 Board

Moderators: terriblefire, Terriblefire Moderator

sety
Posts: 141
Joined: Mon Aug 13, 2018 8:47 am

Re: TF project.

Post by sety »

Sety, out of curiosity where in the world are you located? Do you have the expertise to solder on ic3? Is this something you need the liquid solder and an oven for?
I'm in Australia.

I was planning on using solder paste and flux (both available locally) and with a hot air torch. It shouldn't be too difficult. It's quite satisfying actually, when the grey solder paste hits transition point and goes all shiny and seems to "suck" the component in to place. :)
sety
Posts: 141
Joined: Mon Aug 13, 2018 8:47 am

Re: TF project.

Post by sety »

terriblefire wrote: Sat Nov 17, 2018 4:19 pm The sockets I used were the 121 pin BERG sockets.
Hi TF. I have a TF520 close to completion. Still waiting on a few parts. I'll send a photo once I get some flux cleaner, I'm a little too embarrassed right now as my board looks very messy. :)

Could you please tell me the values of C3 and C4?

Any tips for soldering the PGA socket? Is paste and rework torch okay or should I stop being lazy solder each pin with an iron? The sockets were expensive so I don't want to mess that part up. :)

Cheers,
Stuart
terriblefire
Moderator Team
Moderator Team
Posts: 5449
Joined: Mon Aug 28, 2017 10:56 pm
Location: Glasgow, UK

Re: TF project.

Post by terriblefire »

I don’t know. I don’t support the 520 anymore and I lost all the files in a hard disk failure. There isn’t a magic number that will or won’t work. They’re all between 1 and 22uF
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 11029
Joined: Thu Aug 17, 2017 7:40 pm
Location: Essex
Contact:

Re: TF project.

Post by rubber_jonnie »

sety wrote: Mon Dec 10, 2018 8:28 am
Any tips for soldering the PGA socket? Is paste and rework torch okay or should I stop being lazy solder each pin with an iron? The sockets were expensive so I don't want to mess that part up. :)
Although I haven't built a TF accelerator, I did build a PAK-68/20, which also used a 68020 and the same sort of socket you're describing I think.

You can see it here: https://www.exxosforum.co.uk/forum/viewt ... t=40#p4807.

I manually soldered each and every pin of that socket, and it was quite tough due to the tight pitch of the pins, so if you have got a way of making it easier, then that might be a good way to go.

Only problem I can see with a rework torch is maybe overheating things. I guess if you're experienced with the torch (I'm still learning!) though, you won't have any issues.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
User avatar
8 Bit Dreams
Moderator Team
Moderator Team
Posts: 785
Joined: Fri Nov 09, 2018 7:12 am
Location: Germany

Re: TF project.

Post by 8 Bit Dreams »

sety wrote: Mon Dec 10, 2018 8:28 am
Could you please tell me the values of C3 and C4?
..
Cheers,
Stuart
TF520 boots even without these caps @32Mhz, however i placed 10uF/25v smd's and these are working perfectly
Retro computer hardware & repair in Germany
sety
Posts: 141
Joined: Mon Aug 13, 2018 8:47 am

Re: TF project.

Post by sety »

Yes!!
tf520.JPG
tf520.JPG (71.06 KiB) Viewed 7052 times
Okay it doesn't look like much, but I hear key clicks when I press keys, so 68020 is alive. :)

No disk access yet and it crashes (reboots) at the timeout where TOS starts GEM from ROM because of no disk...

Programming the CPLD was a nightmare. Won't program in Impact GUI but will program in CLI batch mode.

The other weirdness is that it only works if GND and VREF are plugged into the programmer. I measured the impedance and it was 10K, but placing a 10K resistor instead didn't work, so I have NFI right now. =/
terriblefire
Moderator Team
Moderator Team
Posts: 5449
Joined: Mon Aug 28, 2017 10:56 pm
Location: Glasgow, UK

Re: TF project.

Post by terriblefire »

sety wrote: Sun Dec 16, 2018 11:43 am The other weirdness is that it only works if GND and VREF are plugged into the programmer. I measured the impedance and it was 10K, but placing a 10K resistor instead didn't work, so I have NFI right now. =/
If i understand you correct you are expecting the programmer to power the CPLD while its being programmed? if so this is not correct. The board needs to be on and a 3.3v voltage present for anything to program. The programmer does not power the board.

What impedance are you measuring? VREF to ground?

EDIT: By far the easiest way to program these with a Xilinx programmer is to plug the board in.. wire up all 6 wires to the programmer, turn on the amiga and use Impact to program. then reset.

VREF is used by the programmer to check the board is (a) on and (b) so it uses the correct voltage to program a chip. (i.e. so it doesnt cook a chip with too high a voltage).
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
sety
Posts: 141
Joined: Mon Aug 13, 2018 8:47 am

Re: TF project.

Post by sety »

My bad. I was trying to run it with TOS 1.04

Here it is with EmuTos. It's looking a bit healthier. I rekon it's going to work :)
Attachments
IMG_1493.JPG
IMG_1493.JPG (75.61 KiB) Viewed 7009 times
sety
Posts: 141
Joined: Mon Aug 13, 2018 8:47 am

Re: TF project.

Post by sety »

YES!!!!
Attachments
tf520x2JPG.JPG
tf520x2JPG.JPG (48.31 KiB) Viewed 6975 times
TF520x1.JPG
TF520x1.JPG (90.55 KiB) Viewed 6975 times
User avatar
exxos
Site Admin
Site Admin
Posts: 24239
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: TF project.

Post by exxos »

:bravo:
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Post Reply

Return to “TF520 (OBSOLETE)”