QL Pico VGA
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- Over Heated PSU
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QL Pico VGA
Interesting development by Holmatic on forum.tlienhard.com
https://github.com/holmatic/video_if_ql_vga
https://github.com/holmatic/video_if_ql_vga
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- Aurora
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Re: QL Pico VGA
Wow!
I love Marcel's adapter, but I shall definitely be trying out this little project!
I love Marcel's adapter, but I shall definitely be trying out this little project!
Re: QL Pico VGA
This looks great, I was hoping someone might have a go at doing this at some point.
I am guessing that the Rs on the QL side might also provide some meaningful protection for the ZX8301 (given what I've read elsewhere?)
I am guessing that the Rs on the QL side might also provide some meaningful protection for the ZX8301 (given what I've read elsewhere?)
Re: QL Pico VGA
Crucial is the decoupling of the actual video signal from the ULA lines, which is given here.
But only if this adaptor stays connected and the signals can not be touched.
In my experience, electrostatic discharge is a bigger risk than the resistive load conditions on the video lines.
Re: QL Pico VGA
Which, I assume, has to be done before the RGB video connector (and is not on a base QL).
Re: QL Pico VGA
There are alternative RP2040 modules which are smaller, and I designed a PCB to turn it into a miniature QL RGB to VGA converter:
Lots of compliments to Oliver, who wrote the firmware and made it available!
Without doubt, this is the best QL video converter ever!
Resulting in a litlle adaptor, which I will mount inside a D-Sub case.
Since the composite video pin in my QLs is unconnected, I use it for the 5V supply. The converter needs less than 20 mA and a little electronic fuse can be used for protection, in the extremely unlikely case a QL device uses that signal (I have never seen any).Lots of compliments to Oliver, who wrote the firmware and made it available!
Without doubt, this is the best QL video converter ever!
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- Font of All Knowledge
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Re: QL Pico VGA
Hi Peter,
I have been following the discussion on tlienhard.com forum, I did not comment, as I do not speak German.
I have ordered a PICO to make an adapter, but I thought the PICO VGA adaptor was a good idea, your enhancement looks great.
Another execellent item for the wishlist.
I have been following the discussion on tlienhard.com forum, I did not comment, as I do not speak German.
I have ordered a PICO to make an adapter, but I thought the PICO VGA adaptor was a good idea, your enhancement looks great.
Another execellent item for the wishlist.
Regards,
Derek
Derek
Re: QL Pico VGA
Hi folks,
please find attached Gerbers, schematics and placeplan for my Mini VGA board.
At current stage, the VGA HSYNC and VSYNC lines have to be wired according to the following photos: Maybe Oliver will provide alternative IO for regular module pins later. When using HD-Sub with solder buckets, and a PCB is thicker than 1mm, it will not fit between the pin rows. (You see that in my previous post). I recommend to file off 0.3 mm of PCB border in that case. Or use HD-Sub with pins.
Good luck!
Peter
please find attached Gerbers, schematics and placeplan for my Mini VGA board.
At current stage, the VGA HSYNC and VSYNC lines have to be wired according to the following photos: Maybe Oliver will provide alternative IO for regular module pins later. When using HD-Sub with solder buckets, and a PCB is thicker than 1mm, it will not fit between the pin rows. (You see that in my previous post). I recommend to file off 0.3 mm of PCB border in that case. Or use HD-Sub with pins.
Good luck!
Peter
- Attachments
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- qlminivga-1.0-schematics.pdf
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- qlminivga.zip
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- qlminivga-1.0-placeplan.pdf
- (3.55 KiB) Downloaded 416 times