Gotek OSD not working on Atari Hi-Res (wrong refresh rate)

[julianw]

Hi there, I've wired my gotek to my Atari, hoping to use the OSD function in my Atari in Hi-res mode.
Hi-res monochrome is the only mode I can use with Notator.
I'm really happy with the Gotek performance, except the OSD function is not working properly.
Unfortunately the text is garbled, I think it is becuase the firmware is set to 31Khz, and the display needs 35.8Khz

I downloaded the custom firmware with both VSYNC & HSYNC and attached the Gotek to the appropriate place in the circuit.
I experimented with different 'Screen / resolution types'
[40x24 - 31khz] was the closest but the text is still garbled

With the Atari connected using Hi-Res>VGA cable the monitor reports:
Resolution = 640x400
Vertical refresh rate (VSYNC) = 72Hz
Horizontal refresh rate (HSYNC) = 35.8kHz

As you can see the text is displayed but is garbled.

This 35.8Khz horizontal refresh rate reported by the monitor is corroborated by information in the pages below:
https://info-coach.fr/atari/documents/myFAQ.php (VSYNC 71Hz HSYNC 35.8 KHz)
https://www.exxoshost.co.uk/forum/viewt ... 5&start=40 (VSYNC 71.2Hz HSYNC 35.8 KHz)


If possible could we get a custom firmware update with the option set to 35.8khz, would be most appreciated.
I spent a lot of time getting this far, and it would be nice for it to be functioning fully

Thanks
The pictures below explain the wiring for anyone wishing to undertake this in Hi-Res mono mode.

[Jeff]

Can you make a small video to show me the current OSD state at 35 khz ?

EDIT : I think that the HSync delay is just too long, i will short it.

[Jeff]

Custom firmware updated :

Try the 31Khz settings. Think to clear the internal settings after the firmware update (press the right button at power up).

[julianw]

Hi Jeff,

I just got around to trying the updated firmware and it works fine now, I did need to clear the internal setting as you mentioned.
The text is stable and legible now.

Just for your information - When the Gotek starts accessing (exactly 4seconds after selecting the disk image - when the text changes to display Track i.e T:007/255) there suddenly begins a lot of noise in the text, it seems like interference/noise but the text is stable and readable when selecting disk images and that is all I need.

Thanks for the firmware fix, most appreciated

[Jeff]

Good !

I am interested by a picture to see it working in Hi-Res mode.

[julianw]

Hi Jeff and everyone interested hope you are all keeping well,

Sorry for the delay posting these, here are some pictures in hi-res mode, I think the text maybe brighter if I reduced the resistor value, however it is readable and I'm Happy

[Jeff]

Thanks !
(you know that you can use the normal mode now you have the osd ? Use the normal cfg file, or just remove completely the config file !)

[DeckerZ]

I have just come across this thread after much searching. I am keen to have OSD for my Atari STE for all resolutions, well at least for colour for games. What points do I connect my custom firmware Gotek to for low resolution mainly and is there an official guide so I also know what pins on the Gotek to connect as well?

[Jeff]

I have just come across this thread after much searching. I am keen to have OSD for my Atari STE for all resolutions, well at least for colour for games. What points do I connect my custom firmware Gotek to for low resolution mainly and is there an official guide so I also know what pins on the Gotek to connect as well?

The OSD documentation is available there :

https://hxc2001.com/docs/gotek-floppy-e ... splay.html


The STE has the CSYNC signal so you only need 2 wires (the video signal and the composite sync signal).
You can use the pre-built OSD firmware available in the the HxC firmware archive.

If you have an STE with the RF modulator you can find the CSYNC signal on U211 at the pin 6 :

HxC_OSD_Atari_STE_Modulator.jpg (107.5 KiB) Viewed 10304 times