Need help with initial faultfinding on 1040STe

[siriushardware]

Good to know I might be barking up the right tree - I'll order the socket before the weekend and then remove the original socket when I have attained the necessary zen-like level of calm to be able to tackle it without damaging the board.

(I may just cut the plastic frame of the old socket to pieces and then unsolder the pins individually).

[siriushardware]

I had exactly this with an STM - which also had a number of other faults before it worked again. It's worth getting retainer clips for the socket to keep the bugger clamped around the chip too.

The machine is in more or less original as-built condition - I don't think Atari fitted retaining clips originally did they?

Doesn't seem damaged - anyway - won't be too long before the new socket is fitted. Good picture of the clips in that thread you pointed out - I'll have to see if I can get some once the machine is working again.

Dal, where did you get your socket(s)? I got my replacement 68-pin PLCC socket a couple of weeks ago but have only just now had a window of opportunity to take the old one out - I managed to do that nice and cleanly with no damage to either the PCB or the socket. I got the socket out in one piece in the end, but when I came to slip the new socket in and solder it up, something... wasn't quite right!

(See pictures, if I've managed to attach them OK. I set my camera to its max compression and a much smaller x by y pixel size than it is capable of - hope these are not too big).

The original STe CPU socket has the pins in the inner and outer rows staggered / zippered, but the replacement I bought (and every other one I can find so far) has the two rows of pins inline with each other on a 0.1" grid. I have to admit this took me completely by surprise, I had just assumed that all 68-way through-hole PLCC sockets would be exactly the same.

Anyone know where I can get the strange staggered-pin Atari version? UK stockist preferred, but I'll consider any source. Otherwise I'm going to have to put the original socket back in and solder the CPU to the socket pins - I would rather not have to do that.

CPU_out.JPG

Sockets_Both.JPG

Socket_Old.JPG

Socket_New.JPG

[exxos]

A lot of people have been looking for those sockets, myself and others and we all gave up. They simply don't exist! The only source is used ones from old motherboards.

[siriushardware]

A lot of people have been looking for those sockets, myself and others and we all gave up. They simply don't exist! The only source is used ones from old motherboards.

Were this type used in every STe PCB, or just in an unlucky few?

The only other thing I can think of is to put the old socket back in, 'tin' all the cpu pins with solder, put it back in the socket and then apply a superfine pointed iron to each CPU pin to make the solder re-flow to form a soldered connection to the corresponding socket contact. I would have to be pretty desperate to do that, as the odds of melting the socket frame in the process would be quite high.

[siriushardware]

I had the machine running perfectly all night long last night, with an adaptor PCB originally meant for mounting an AT_Once PC emulator on top of the CPU jammed down on top of it, with its pin contacts pushed into the holes on the outsides of the CPU socket contacts. The PCB I'm talking about is just an adaptor to allow a 64-pin DIP At_Once emulator PCB to be mounted on top of a PLCC CPU. There is nothing electronic on it.

As long as I had that adaptor PCB fitted, it made the CPU socket contacts lean in further towards the CPU pins and grip it more tightly and the machine ran reliably. As soon as I took that adaptor off, it either stopped working or worked very intermittently. I could just leave the adaptor fitted for ever (easy, costs nothing), but I wouldn't consider the STe to be properly fixed if I did. Also, the AT_Once adaptor obstructs the flow of air from the top of the CPU, making it run hotter than necessary IMO.

As the CPU is currently not fitted (or fittable), I unfortunately can't answer / follow up on your diagnostic suggestions for the time being. Thanks for the offer of parts, which I may need to take you up on.

[Dal]

I must have been lucky as I had a suitable socket in a lucky bag from Maplin.

[siriushardware]

I must have been lucky as I had a suitable socket in a lucky bag from Maplin.

Uhhhhh... (You lucky s*d!).

I'm working on this problem... I'll be back eventually.

[siriushardware]

I finally got some info back from Cricklewood about their sockets - at the time of writing this (February 2015, in case someone reads this in three years' time) the only 68-pin PLCC sockets they have are the commonly available 'inline pin' type, and not the 'staggered pin' type needed by the STe.

So, still looking...

[firyembers]

The socket (properly called as I believe a plcc 68 socket)you are after I found some years ago sourced from Hirose which I used to add a co-processor to mega ste
It's a HC3-68ST
Just had a quick look on their site with no success, and looked around equally with nothing found but further datasheets and have attached the Hirose pdf
Anyway I have one I can send you to confirm, it's a plcc socket 68 staggered type through hole.
pm me your address and it will be yours shortly.

HC3-84S_2.pdf

[siriushardware]

Anyway I have one I can send you to confirm, it's a plcc socket 68 staggered type through hole.
pm me your address and it will be yours shortly.

I sincerely appreciate the offer but the socket in the PDF datasheet you referenced is the widely available inline-pin type, not the staggered type. If this is the type you have I'm afraid it will not fit in my STe.

As a matter of interest, can you take a photo of your spare socket and post it here? I'm wondering if Atari switched to the standard modern (inline pin) type of socket by the time they were making the Mega STe. I posted pictures of both sorts earlier in this thread, take a look back and look at the difference.

[siriushardware]

As I stated earlier in the thread, the plug over board was never fitted in the STe originally. I only fitted the DIP to PLCC header adaptor part of it into the STe after the machine had failed and found that fitting it actually made the machine work, hence the conclusion that the socket on its own was not making proper contact with the chip.

[siriushardware]

Best Electronics (California, USA), as seen on their highly retro-looking website here:-

http://www.best-electronics-ca.com/

-do have the Atari-special PLCC sockets. I didn't find them listed on the website though, it's one of the items you have to email them about.

I have to say the proprietor, Brad Koda, is incredibly courteous and helpful.

The sockets are described as 'Best High Insertion Force PLCC sockets', available in
68-pin @ 7.00 USD
84-pin @7.50 USD

Prices were correct at the time of writing this, February 2015. If you are reading this in five years' time, price and availability may have changed by then.

I've ordered, so hopefully there will be one of each on the way to me soon. Minimum order from them with a CC is 20 USD, or 50 USD if using Paypal, so I ordered a couple of other items to make up the minimum value. I paid for US priority mail in order for the order to be insured, so this isn't coming cheap. I'll report progress when they arrive - probably in about 1-2 weeks.

[firyembers]

It is the staggered type I have.As per page 220 bottom left 68 pin (staggered)
Oh! I never saw those pics you posted,but yes it will fit the pcb pic you sent

[siriushardware]

It is the staggered type I have.As per page 220 bottom left 68 pin (staggered)
Oh! I never saw those pics you posted,but yes it will fit the pcb pic you sent

My apologies, you are of course correct - although most of the sockets illustrated in that PDF are the common / modern inline pin type, the one illustrated bottom-left of page 220 of that PDF is indeed the staggered-pin type, I missed that when I looked at it originally, sorry.

The problem is I've had quite a few people direct me to sources for 68-pin PLCC sockets but when I followed up they were invariably the inline-pin type, so I was beginning to give up hope, sorry about that. Thanks for trying to help, anyway.

As you may have read one or two posts back, I took the plunge and ordered two sockets (one for the CPU, one for the 84-pin Shifter) from Best Electronics in California. I think if anyone in the world is going to manage to send me the right sockets it would probably have to be them, but please hold on to yours and keep it handy just in case the ones that arrive are inline-pin...

[Mstepansky]

Hi guys. I need your Atari STe video tech expertise to diagnose or resolve this apparent video sync pulse problem. I have Atari 4160STE here (USA, 60 hz) with 4 MB ram. It has FM (tested) and RGB (not yet tested) port. It was part the Atari Science Discovery package back in 1990 or so. This is a 4MB version installed by Atari Inc. I bought it on ebay in December 2014.

When I boot up, after stable white screen, the TOS ROM 1.6 rainbow (1989) appears to work fine, but it looks like there is a apparent problem with video sync screen. I am not sure if it is a blitter, video shifter or GLUE IC chip or even TOS is at fault or if chips need reseating?

Root-cause analysis: If you watch the screen (low res mode in FM, not yet test in high rez mode via rgb-to-vga cable to LCD monitor), the screen display shifts "down-up" by 3 scanlines, 2 times, before it pauses for about 1 second, then repeat itself. In that order.

Its timing looks like this: down-up, millisecond pause, down-up, pause 1 second, so on. How do I fix it? Which IC components might be faulty? I was reading various posting here, and it seems to point to Glue chip, and other says metalic dust crosses over the glue chip socket, etc, not sure... It is unlikely that our WiFi router would be affecting this video sync, right?

Also, I notice something else. when I open a GEM gui-window, the window frame itself looks like it is speeding up as it redraws (refreshes) lines within the window frame abnormally when resizing from large to small. It happens when I am holding and moving on the lower right corner to resize window. Any advice? I have not yet open the computer.

I m hoping it is as simple as reseating or replacing glue chip or other chips. I will check part number for DMA IC chip to be sure it is the latest one ( hard drive issues for some ultraSatan users who use STe with older DMA chip). Thank you for helping me. Mike.

[siriushardware]

Hello Mike - your sync problems and your window redraw anomaly, if it is one, sound like separate issues. If you don't mind can we take the apparent sync problem first?

Your post seems to say that so far you've been using the RF (you referred to it as 'FM', the modulator) output?

What you are using for a display? CRT or flatscreen type TV? If possible, what brand / model?

Can you please try using a composite video signal and / or RGB signal connection between the STE's monitor output and the display to see what difference, if any, either of those modes makes?

[Greenious]

(Old STs were sold in different variants in the beginning. The plain old 520 ST had external drive and no TV out. STFs (F is for floppy) had a diskdrive built in. STMs had external drive but TV out and STFMs had both TV out and built in diskdrive... Pretty quick the only thing selling was STFMs though, and the STE was never sold like that. They all had built in drives and TV out. So technically there is no "FM" unit. There is however a TV modulator unit)

Have you tried another TV? If TV out is working, so is RGB since the TV out is made from those signals. If it works with RGB, it's likely the modulator unit that is faulty. It's a MC1377P if memory serves me right. From the description I suspect there is some kind of problem with your hsync/vsync signal, or composite sync. It really would help if you could test the "clean" RGB signals.

The quick and dirty "reseating" can be done using the infamous 2 inch drop. Turn off your atari, lift it up about 2 inches and drop it on the table. Fixes a lot of problems related to oxide and chips needing reseating. Or, if you prefer, get your screwdriver and open it up...