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VR177x (WD1772 replacement)

Posted: 18 Jan 2024 10:55
by rubber_jonnie
It looks like vRetro in New Zealand have come up with a replacement for the WD1772. I don't think it has been released yet and isn't in the store, but I wonder if it is running at faster clock speeds like the Ajax.

Re: VR177x (WD1772 replacement)

Posted: 18 Jan 2024 11:33
by Gooeyblob
Yes - " is designed to operate at both 8MHZ and 16MHZ the signal at the clock input pin is measured and the operating frequency set internally to match. If there is no clock signal present then if the clock input is 0V then the frequency internally is set to 8MHZ, if the clock input is +5V then the frequency is set to 16MHZ. This means a very simple interface (no external oscillators needed) can be used to change from DD to HD. In fact every gotek can be programmed to set HD/DD status on pin 2."

Re: VR177x (WD1772 replacement)

Posted: 18 Jan 2024 11:42
by rubber_jonnie
Gooeyblob wrote: 18 Jan 2024 11:33 Yes - " is designed to operate at both 8MHZ and 16MHZ the signal at the clock input pin is measured and the operating frequency set internally to match. If there is no clock signal present then if the clock input is 0V then the frequency internally is set to 8MHZ, if the clock input is +5V then the frequency is set to 16MHZ. This means a very simple interface (no external oscillators needed) can be used to change from DD to HD. In fact every gotek can be programmed to set HD/DD status on pin 2."
Sounds fantastic, thanks for the info :)

Re: VR177x (WD1772 replacement)

Posted: 18 Jan 2024 12:08
by alexh
This is the only reference I could find online :

https://atarionline.pl/forum/comments.p ... e=1#Item_0

This is their homepage. Looks like they make IC replacements for various classic computers, concentrating on Sinclair Spectrum

https://www.vretrodesign.com/

The developer is called Charlie Ingley

Re: VR177x (WD1772 replacement)

Posted: 18 Jan 2024 12:18
by HigashiJun
Very interesting.

Re: VR177x (WD1772 replacement)

Posted: 18 Jan 2024 12:33
by chronicthehedgehog
alexh wrote: 18 Jan 2024 12:08 https://www.vretrodesign.com/

The developer is called Charlie Ingley
I bought a ZX ULA replacement from him in the past. Quality stuff.

Re: VR177x (WD1772 replacement)

Posted: 18 Jan 2024 12:51
by stephen_usher
Yeah, it's Charlie Ingley.

Re: VR177x (WD1772 replacement)

Posted: 18 Jan 2024 13:06
by troed
Surprising that Gotek has pin 2 as an output. In the spec (and in the world of real floppy drives) it's an input.

However, it should work fine modifying the drives we know how to do it on - so this would support real drives too,

https://blog.troed.se/2017/01/20/the-ta ... i-mystery/

Re: VR177x (WD1772 replacement)

Posted: 19 Jan 2024 07:34
by HigashiJun
troed wrote: 18 Jan 2024 13:06 However, it should work fine modifying the drives we know how to do it on - so this would support real drives too,
That would be great.

Re: VR177x (WD1772 replacement)

Posted: 22 Jan 2024 14:59
by arf
Gooeyblob wrote: 18 Jan 2024 11:33 is designed to operate at both 8MHZ and 16MHZ […]"
Do you know by chance whether a 32 MHz operation (for ED floppies) is planned? That’d be my usage scenario.