MegaSTE repair

[atari030]

Found one, free same day delivery for Melbournistan. I was planning on an iron upgrade too, so that works well. Cheaper than the other one locally too. Ripper.

https://www.radioparts.com.au/product/3 ... gKAuPD_BwE

[troed]

The Duratool is sold as other brands so you might find it that way. I can't recommend it enough.

I have the same model and I agree.

/Troed

[atari030]

Ordered. I should have it tomorrow. Time to retire the solder sucker and hand iron. :D

[rubber_jonnie]

Nice

[atari030]

Yin and yang. The station is out of stock. :cry:

But, I decided to flick the board on on my way out the garage to work.

I had gone pretty hard cleaning the board and reflowing so when I saw this it put a spring in my step. Copped four bombs, either floppy, controller or the Yammy I guess. All of which shouldn't be too hard to sort out.

Kapla

IMG20200722082656.jpg

[DoG]

You get 4 bombs in TOS 2.06 when no floppy is attached but it seems you already know that?

[atari030]

Yeah, it didn't like the drive I had used. An SMD300 works a treat. It still has problems, sysinfo throws up 4 bombs and a demo disk I threw in, three bombs. A diag cart would be a game changer right now.

Still, this board hasn't kicked over in 20 years, so onwards and upwards.

[atari030]

A bit more progress, the desolder station fell through. So I'm working to secure another local option. Meanwhile, back at the ranch....

I managed to get Sysinfo working. I wanted to test the cpu @16mhz so I modded a new TEAC drive and set up a boot disk with Xcontrol. It promptly crashed on boot, 2 bombs. Righto, so deduction. As I had deleted the control.inf file it couldn't be a CPX. I dropped an prog in the auto folder, 16mhz aok. I figured it must be the RTC. Some of the joints were pretty crappy so I reflowed to no avail. Then I replaced C402 which looked like a leg had come adrift. Rebooted and bazinga. Sysinfo kicks off. :D

I apologise for being a bit nuts over this, but this is one of the machines I was given as spares that sat in my shed for 15 years. I always thought it was a basket case and it was meant to be a donor. I never expected to get it working again.

I've jotted down the jumper's to save me having to google them again.

ATARI MegaSTE Jumpers

ROM jumper settings
Part Type W201 W202 W203
27256 Don’t care 1 and 2 N/C
27512 2 and 3 2 and 3 N/C
57101/27C1000/531000 2 and 3 2 and 3 2 and 3
27010/571000/27C1001 1 and 2 2 and 3 1 and 2

W401, W402 – Internal/External drive A/B
J401 – Battery
J290 – Power LED
J291 – External fan
W3 – FPU enable

DIP Switches
1 – 6 - ?
7 – HDD enable
8 – DMA Sound disable

[rubber_jonnie]

You mention the SMD300 and I expect it should work as a 720KB, unless yours, like mine came with a 1.44MB FDD factory fitted.

Might be worth a look at the 1.44MB install guide to be 100% sure it has everything it needs. I've included the FPU install guide in case you're interested.

[atari030]

I changed it over to a new TEAC as the SMD was stripped from a PC a few years ago and a tad grotty. I have a decent collection of floppy drives because I knew this day was coming and I grabbed as many from work as I could. ;-) It is all GALled (002) up for 1.44. No AJAX, but the 02-02 hasn't missed a beat with the new drive.

I've still got some problems to iron out, looks like DMA. C398789-001A PLCC type is flakey. I will have to recap the whole shooting match first, I think. Changing one cap can't be a coincidence. I will recap, and then hopefully post will settle down so I can sort a diag cart out.