TT030 Reset Issue

[MacTech05]

Exxos,

I have a TT030 that has been working great. Turn it on and it boots right up.

I was setting up my Ultrasatan drive. Partitioned with HDDriver 12, restarted (warm reboot, not power off), all partitions on the SD card in the Ultrasatan still there. But there is an issue with the Ultrasatan once it is powered off and back on..partitons gone, but not really. I will explain that later.

The main issue I have is that later, after re-partitioning of the SD card in the Ultrasatan and powering the TT down, when I turn the TT back on, it did
not boot. The monitor light was green, but once I turned on the TT, the monitor light went amber (yellow). So, I said "what the hell" and pressed the Reset button on the TT and the TT booted right up to the Desktop. When I say "pressed the Reset button, I do not mean a quick press, I mean I have to press and hold the Reset button for a couple of seconds. So, I again said "what the hell". I had not heard of the TT having this issue, as we have seen on the other STs. The solution, per your Mandatory Fixes, is to replace the Electrolytic Capacitors in the Reset Circuit.

My questions are:

1. What is the fix on the TT?
2. Do I need to replace electrolytic capacitors in the TT Reset Circuit? I am not sure of the location of the Reset Circuit on the TT motherboard.

3. Could the Reset switch be bad?

I appreciate help/recommendations you or anyone can provide to help me solve this issue.

Now, the Ultrasatan. I do not think the Reset issue had anything to do with the Ultrasatan. But, I am not ruling anything out. The original issue I was having with the Ultrasatan, was once I turned of the TT and the Ultrasatan, turned the Ultrasatan then the TT back on, the partitions I created on the SD card in the Ultrasatan, were gone. I re-partitioned several times and all is good until I turn off the TT, then the Ultrasatan. Every time, in this case, when I turn the Ultrasatan back on and then turn on the TT, the partitions are always missing.

However, I decided to open the HDDriver Utilites and selected "Rescan Devices". Then I exited HDDriver Utilites and the partitions were there, including the folder I created on the first partition and the files I copied to that folder. But I have to do this everytime I power down the Ultrasatan. I do not understand what is happening with the Ultrasatan. I have not read about this happening anywhere.

By the way, the Ultrasatan does the same thing with my Mega STE.

Thoughts? Please help me out if have any ideas.

Thank you!

Randy

[Cyprian]

My TT was completely dead. I randomly checked the reset button and it was dead. I replaced it with ST (from a dead mobo) one with a success.

[MacTech05]

Cyprian,

Thank you for the advice. I have suspected from the beginning that it may have something to do with the Reset switch, since all has been great, until 2 days ago, when I turned on the TT and it did not boot up. So, in a "what the hell" shot in the dark I pressed the Reset button and bam, the TT boot right up. Now I have to press the Reset button every time I turn the TT on.

Replacing the Reset switch is probably the best bet, at this point.

Again, thank you!

Randy

[Steve]

Don't want to scare you, but this happened to me once. My TT would not boot unless I pressed reset (and my TT was already re-capped)

Turned out that the Noctua fan I put in my PSU wasn't running fast enough, something blew in the PSU and it was sending 7v down the 5v rail.

Got the PSU fixed and then it booted fine. I was very lucky to notice and test my PSU output!

(I now run my Noctua on full speed setting)

The moral of the story is: don't just assume what the problem and fix is :)

[MacTech05]

Steve,

Thank you for your response.

I have had an uneasy feeling about my power supply. In fact, as a think about it, I believe it makes the most sense. I should listen to my instincts. I do have a power supply in a Mega STE I am not using and is the same power supply as the TT. I will go ahead and swap out and see what happens. Hopefully that will do it.

It is worse, by internal SCSI hard not stopped booting yesterday. It spins up, but does nothing.

I won't turn it back on until I swap out the power supplies. If that does correct the problem with having to press reset every time I start up the TT, that will be progress and go from there.

Again, thank you very much.

Randy

[MacTech05]

I tested my PSU and all of the 5V supply cables were steady at 5.10 VDC. This is how I tested the PSU output:

I turned on the TT and observed the voltage on each red wire at the main PSU to motherboard connector as it tried to boot, with a disk in the floppy drive and the hard drive connected. All 5V supply voltages measured was steady at 5.10 VDC. Sometimes it would vary between 5.10 VDC and 5.11 VDC, but it would settle at a steady 5.10 VDC.

I also checked the 5V supply in the floppy drive power cable, as well as the 5V supply to the internal SCSI hard drive. Both were a steady 5.10 VDC.

This makes me want to say the PSU seems to be functioning as it is supposed to do.

I also reseated my four TOS 3.06 ROM chips. Results the same. I have to press the Reset button for the TT to boot up. Not certain as to what to test next. I thought about the Reset switch, but I do not know if that would make sense. I suppose I could replace it, as it is a pretty inexpensive part to purchase.

If you have any additional suggestions as to additional tests I need to do, please let me know.

Thank you!

Randy

[exxos]

I'd suggest adding a new cap on the reset circuit caps to see if it helps.

[MacTech05]

Exxos,

I was thinking that as well. Do you happen to have a photo or diagram of the TT motherboard that points out where that reset circuit is located, as you did in the mandatory fixes section? It is not normally marked on the motherboard. How would I know for sure? I will try to find a copy of the TT service manual with, hopefully, schematics included.

Also, suggested caps to replace the old ones, or just replace with new ones of the same specs?

Thank you.

Randy

[stephen_usher]

There are a number of TT motherboard revisions with very different layouts. Which revision do you have?

[exxos]

I was thinking that as well. Do you happen to have a photo or diagram of the TT motherboard that points out where that reset circuit is located, as you did in the mandatory fixes section? It is not normally marked on the motherboard. How would I know for sure? I will try to find a copy of the TT service manual with, hopefully, schematics included.

Also, suggested caps to replace the old ones, or just replace with new ones of the same specs?

I have never owned a TT. So cannot tell you anything about it or any sort of fixes for it. All my work is on STFM/STE.

But the schematics are here.

viewtopic.php?f=31&t=100

It looks like the reset circuit has 2x 10uF so you could just solder another 10uf on top of those and see if it makes any difference or not.

rs.PNG