27C400/27C800 EPROM emulator

Any 8bit repairs, images, cool things, upgrades etc.
Zak_G
Posts: 3
Joined: Sun Oct 06, 2019 2:32 pm

Re: 27C400/27C800 EPROM emulator

Post by Zak_G » Tue Oct 08, 2019 12:08 am

Hi Chris

I'm loving the idea you are developing, I'm just getting back into the retro vibe with my a600 and was wondering when and how much of my money you would want.

Happy to volunteer as a tester if you still need one ;)

Regards
Zak

cmorley
Posts: 28
Joined: Tue May 28, 2019 5:46 pm

Re: 27C400/27C800 EPROM emulator

Post by cmorley » Tue Oct 08, 2019 12:09 pm

Zak_G wrote:
Tue Oct 08, 2019 12:08 am
I'm loving the idea you are developing, I'm just getting back into the retro vibe with my a600 and was wondering when and how much of my money you would want.
Thanks for your kind words. The prototype boards seem to be working well for people so far.

The next step is to finalise the hardware layout and order some PCBs for the release candidate board. I will do that very soon. I'll probably end up ordering 40-50 PCBs & hand assemble those. Parts are always more expensive in low quantities so at a guess we'd be in the £20-£30/€22-35 ball park. If I order this week then I might have boards ready in early November. Firmware upgrades to follow as people report problems or suggest features.

Ultimately if they sell then I want to try to buy assembled from China in larger quantity to get the cost down. I'd need to order hundreds in one go which is a big upfront cost (few £k :O) and a bit of a risk. I need to develop an automated program & test for this to be practical too... I have a plan to do this with an STM32 and/or CPLD.

So if you want one cheap then you need to wait for the bulk order. If you want one sooner and support the development then hopefully next month I will have a bunch ready.

User avatar
PhilC
Moderator
Moderator
Posts: 2066
Joined: Fri Mar 23, 2018 8:22 pm

Re: 27C400/27C800 EPROM emulator

Post by PhilC » Tue Oct 08, 2019 2:41 pm

Sign me up for one for your next batch please, don't mind supporting your efforts :)
If it ain't broke, test it to Destruction.

Maximilian
Posts: 103
Joined: Thu Feb 28, 2019 5:02 pm

Re: 27C400/27C800 EPROM emulator

Post by Maximilian » Tue Oct 08, 2019 5:26 pm

Nice product,

Certainly interested in at least 1.
Will the firmware be open source?, later on I would like to add features myself if possible.

Zak_G
Posts: 3
Joined: Sun Oct 06, 2019 2:32 pm

Re: 27C400/27C800 EPROM emulator

Post by Zak_G » Tue Oct 08, 2019 9:41 pm

Hi Chris

Thanks for the response. Is there a how to use it guide for us to read while we wait in line?

Also putting 2 & 2 together I went to Boobip.com, howcome there's no coming soon section for this emulator on the website?

If it helps the cause I'm happy to put down a deposit for one of the next batch you are making.

Regards

Zak

cmorley
Posts: 28
Joined: Tue May 28, 2019 5:46 pm

Re: 27C400/27C800 EPROM emulator

Post by cmorley » Mon Oct 28, 2019 12:16 pm

I've been making a few minor changes to the PCB layout for the release candidate version. I'll order up some PCBs from JLCPCB - because they are the best value for 4-layer boards. The quality is OK for the price IMO. I'll then hand build some more while I investigate getting them bought in fully assembled.

There will be plenty for all forum people who've expressed an interest from this batch. Price I don't know yet.

So far so good in testing. It works in every machine it has been tried in.

Some grief with some terminal programs but that's because I think many do not check the bytes sent return value from the system's write() function - they assume all succeeded or whole buffer failed. When the USB is NAKing (stalled) I think the OS (both Windows and MAC) will return a partial send so badly written terminals fail. e.g. TeraTerm doesn't work. SmarTTY works perfectly.

cmorley
Posts: 28
Joined: Tue May 28, 2019 5:46 pm

Re: 27C400/27C800 EPROM emulator

Post by cmorley » Mon Oct 28, 2019 12:19 pm

Zak_G wrote:
Tue Oct 08, 2019 9:41 pm
Is there a how to use it guide for us to read while we wait in line?

Also putting 2 & 2 together I went to Boobip.com, howcome there's no coming soon section for this emulator on the website?

If it helps the cause I'm happy to put down a deposit for one of the next batch you are making.
No guide sorry. I'll write the documentation when the firmware interface is stable. Same for the website - I don't enjoy doing websites so I only put things on which are finished.

No need for deposits but thanks for the offer.

cmorley
Posts: 28
Joined: Tue May 28, 2019 5:46 pm

Re: 27C400/27C800 EPROM emulator

Post by cmorley » Mon Nov 18, 2019 1:12 pm

Right I have been super busy in meat space for the past three weeks.

I have finished tidying up the PCB to what I think will be OK for manufacture. So I have now just ordered more PCBs from JLCPCB.

The firmware is functional - it has moved on a bit since I sent Chucky his test units. It needs some costmetic work and there are a few extra features on the list to add but otherwise it is working & most importantly fits in the MCU!

cmorley
Posts: 28
Joined: Tue May 28, 2019 5:46 pm

Re: 27C400/27C800 EPROM emulator

Post by cmorley » Fri Dec 06, 2019 3:26 pm

The issue D PCBs arrived today. :)

This is hopefully the layout I will get assembled bar a few minor silk screen adjustments.
Photo0877_800.jpg
Photo0877_800.jpg (144.89 KiB) Viewed 154 times
I will hand solder these boards so anyone who wants one can have one from this batch. I need to sort out a pogo pin programmer & tester for them :S

cmorley
Posts: 28
Joined: Tue May 28, 2019 5:46 pm

Re: 27C400/27C800 EPROM emulator

Post by cmorley » Wed Dec 11, 2019 6:55 pm

I am working on tidying up the firmware on this project. FLASH space is a bit tight on the MCU so I put a string table inside the CPLD 8-)

This means that if I shove 90%+ of the strings into the string table then the UI could be translated... is there any point? Just because you can do something doesn't mean you should!

What do people who's first language is not English think?

Post Reply

Return to “8 BIT CORNER”