Random hardware ideas!

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Dave
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Re: Random hardware ideas!

Post by Dave »

The only reason I can imagine for not wanting to use a QL-SD is the need to use an older QL OS than Minerva. I can't think of a single reason why a person would want to do that.

I will send you (Doug) a backplane, Q-Buck regulator (it will help keep the PSU and QL cool when you run everything off that old power supply!

I've been scaling back my hardware ambitions, particularly since Tetroid is doing a good job of releasing hardware I would have made, far more quickly.

I only have a couple of smaller scale projects actively developing now. They're things Tetroid hasn't released or announced.


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Cristian
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Re: Random hardware ideas!

Post by Cristian »

Peter wrote:
Doug wrote:I just want to be able to plug my QubIDE and Gold Card into the QL at the same time, in order to be able to run floppies and a hard disk on one machine at the same time.
Out of curiosity: What is the advantage of this much larger solution over QL-SD, which is also Qubide on SDHC card, just as container in FAT32, not raw?
Only the more mature driver?
QL-SD may not work reliably with Goldcard


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Peter
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Re: Random hardware ideas!

Post by Peter »

Dave wrote:The only reason I can imagine for not wanting to use a QL-SD is the need to use an older QL OS than Minerva.
This is just a question of EPROM contents. Replace the lower 48K with QDOS and voila. ;)
In effect, the QL-SD is a two-in-one solution, EPROM adaptor for the OS plus SDHC interface. It does not restrict the OS (other than the work to program an EPROM).
Cristian wrote:QL-SD may not work reliably with Goldcard
Good point. However, experience showed that QL-SD Is working fine on many GoldCard systems. I noticed that my own GoldCard QL was electrically instable in general, even with no QL-SD at all. My conclusions could not be generalized.

I would, however, keep up my warning regarding SuperGoldCards, which definitely causes more ringing and crosstalk on the QL mainboard signals.

Peter


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Pr0f
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Re: Random hardware ideas!

Post by Pr0f »

Was thinking about a ROM emulator that could plug into DIP28 socket or into a cartridge for the ROM port, with a RAM on board, and the ability to populate the RAM with an Image from an SD / Micro SD card.

A small OLED display could act as the menu, allowing selection of the ROM image required, and size of ROM image. A toggle wheel or couple of buttons could act as the selection for the menu.

A small battery backup circuit could provide non volatile memory protection, and power a small micro to do the leg work. RAM chip could be loaded by shift registers clocked out from the micro.

It's quick and dirty, but could be a useful tool for playing around with the QL and add on cards.




Inspired by the virtual CD rom drives we use at work to reimage machines...


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Peter
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Re: Random hardware ideas!

Post by Peter »

If you mean implemeting a loader which copies a ROM image from SDHC card to ROM emulation area, this can be done by the 68008 itself. It is what the Q68 actually does.
(Of course the loader needs to move it's own code somewhere outside the emulated ROM area before copying.)

It is probably better to make the SDHC card directly accessible for QL side, not just by a microcontroller. That also gives you the option of a QL-SD style "harddisk".

From Q68 experience, I think separate LED display is not needed much. The loader can display infos on the QL screen.

To have shaodw RAM at $0 would be nice, in principle allowing SMSQ/E on the QL.

Peter


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Pr0f
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Re: Random hardware ideas!

Post by Pr0f »

It was more thinking along the lines of testing hardware plugins against multiple rom versions, but you could also use it as the ROM in the interface itself. In fact it could easily be non specific to the QL, but just be usable anywhere a ROM would be used.

The idea of the SD card is the storage capacity, small size and relative ease of reading by a micro.


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Doug
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Re: Random hardware ideas!

Post by Doug »

Dave wrote:I will send you (Doug) a backplane, Q-Buck regulator (it will help keep the PSU and QL cool when you run everything off that old power supply!
Thanks Dave, message me the details and I can send some funds your way!


SM7I
ROM Dongle
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Re: Random hardware ideas!

Post by SM7I »

Hi Dave, I sure want an extender too :)

//Johan

Dave wrote:I got enough interest - five people contacted me about the mini backplane - that I popped into my favorite PCB designer and freshened up the design a little.

The card fits inside a QL and supports three positions. Two positions face left and one faces right, upside down over the CPU. I don't personally recommend that you use all three positions with old cards that suck juice and spit out heat. However it does make it perfectly reasonable to have a newly minted Trump Card and QubIDE with CF slot just above it facing left. Alternatively, you could have the Trump Card face left and the IDE card face right. As long as the total current draw of the cards is under 500mA everything is fine.

The card is TINY, 96.3mm x 20.6mm. I left as much room as possible around it to allow air to circulate in the QL case. It will come with two protective plastic shields so a top card can't short against a bottom card, or an inverted card can't short against the metal keyboard backplate.

Screen Shot 2017-05-01 at 11.44.12 PM.png

I should get the PCBs and have everything assembled in around three weeks. then I'll work out my costs and sell them at cost price. I'll post photos and so on then. I will only be making 25 of these, and have parts on hand to make 8 until I order more male DIN41612 connectors.

If anyone has requests for a custom backplane, I can do something for you.


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