Weird Gotek problem in an STE?

[RB80atari]

Hi all,
I have a weird problem with a Gotek floppy emulator in my STE, its an upgraded Gotek with flash floppy an OLED screen and a rotary encoder.
First of all the gotek is working fine because i can power it from another 5V power source that is not the atari and it works fine...
OK so when i connect the Gotek to the STE with *only* the power cable going from the STE motherboard to the Gotek and power on from cold, all i get is garbage on the gotek screen- its all scrambled pixels, this is with the 34 pin floppy cable unplugged and only the power cable from the STE motherboard going into the Gotek.
Now, if i unplug the Gotek drive whilst the Atari is **turned on** and then reconnect the floppy power cable again, still while the Atari is turned on, the Gotek works ok, the screen comes on like normal and i can see and select the different disk images.
So its like the STE is not powering up quickly enough for the Gotek to run properly, i checked the voltage on the floppy cable and its good 5V, but im thinking the 5V line is not coming up quickly enough for the Gotek to work from a cold start?
I have literally just recapped the power supply today- all 7 electrolytic caps, so its not the psu caps, so something somewhere else is causing a problem, any ideas what i should be checking next??
BTW i had this problem before i recapped the power supply, so its nothing to do with that and the caps i used were good quality and the right value.
Cheers, Bob

[Hellraiseruk]

What happens if you press the reset button on the back? In other words, gotek fully connected and powered on and then hit reset?

JD

[RB80atari]

Hi, its still scrambled after pressing the reset button.
Only way to go get it to work in the atari at the moment is to unplug the floppy power cable from gotek and then reconnect it while the Atari is turned on.
Ive not pulled the motherboard out to look at it, but is there any components between the psu and the floppy power cable, does it feed directly off the psu 5v/12v lines?

[Hellraiseruk]

Has that exact same gotek previously worked fine on this exact same STE, or has it always behaved like that? Which firmware and revision is installed on it?

JD

[Hellraiseruk]

Hi, its still scrambled after pressing the reset button.
Only way to go get it to work in the atari at the moment is to unplug the floppy power cable from gotek and then reconnect it while the Atari is turned on.

That is odd. If it was down to power not coming up quick enough, and the gotek was connected with power and data, I'd expect the reset button to reset the drive and for it to work. Is the drive usable when the lcd display is corrupt, or is it not recognised?

JD

[RB80atari]

hi, ive only recently installed it, it was doing it before the psu recap so i suspected the psu would be to blame, so recapped it today and its still the same- so that didnt fix it.
I think its the latest version of flash floppy, cant remember now. But im only powering the Gotek up with the atari at the moment, the 34 pin ribbon cable it not connected so its not sending/recieving data, so the only reason the screen could be scrambled is due to a power problem
If i power it off a different 5V source it works no problem, so its something on the atari

[Badwolf]

OK so when i connect the Gotek to the STE with *only* the power cable going from the STE motherboard to the Gotek and power on from cold, all i get is garbage on the gotek screen- its all scrambled pixels

I'm investigating this exact problem at the moment and I have the same suspicion it's slow power-on.

The thing is I'm using a new PSU which I know to have a soft-start (about 350ms, empirically), but it sounds like you have an original PSU? They don't exhibit a soft start from what I can tell.

IMG_8312.jpeg

Gotek remains fully functional, it's just the screen that's messed up. I therefore surmise it's the screen more than anything else.

What I've not yet tried is to see what happens if only the power lines are connected to the OLED (ie, disconnected I2C). If the problem doesn't exhibit then, it could just be a delay to initialisation is required in the Flashfloppy firmware.

BW

PS: also worth mentioning the OLED is presumably being powered through the Gotek's 3V3 regulator rather than direct from the 5V rail, so that could be a factor too.

[RB80atari]

Hi,
Thats interesting, thanks.
What PSU are you using there with the soft start?
I had assumed that the drive wouldnt work when i saw the screen scrambled, interesting you say it works and its only the OLED thats affected.
I had another STE, with the same model PSU that id also recapped (same caps) and another gotek exactly the same spec and it worked fine..
I havent pulled the motherboard out to have a look at it, but is the floppy cable running straight off the psu with no components inbetween?
Apart from the psu caps is there any other components on the psu that might be worth changing that might cause this?
Cheers

OK so when i connect the Gotek to the STE with *only* the power cable going from the STE motherboard to the Gotek and power on from cold, all i get is garbage on the gotek screen- its all scrambled pixels

I'm investigating this exact problem at the moment and I have the same suspicion it's slow power-on.

The thing is I'm using a new PSU which I know to have a soft-start (about 350ms, empirically), but it sounds like you have an original PSU? They don't exhibit a soft start from what I can tell.


IMG_8312.jpeg


Gotek remains fully functional, it's just the screen that's messed up. I therefore surmise it's the screen more than anything else.

What I've not yet tried is to see what happens if only the power lines are connected to the OLED (ie, disconnected I2C). If the problem doesn't exhibit then, it could just be a delay to initialisation is required in the Flashfloppy firmware.

BW

PS: also worth mentioning the OLED is presumably being powered through the Gotek's 3V3 regulator rather than direct from the 5V rail, so that could be a factor too.

[Hellraiseruk]

Look at the release notes for v3.41:-

https://github.com/keirf/flashfloppy/bl ... EASE_NOTES

Might this be the problem?

JD

[RB80atari]

Thanks for that,im running 3.41, i hadnt read the release notes- so clearly an issue.
Odd that my other STE with the same PSU version, also recapped had no problem with the gotek.

Look at the release notes for v3.41:-

https://github.com/keirf/flashfloppy/bl ... EASE_NOTES

Might this be the problem?

JD