Cloning an MIF ISA Card

[Bryce]

Oooo look I didn't have time to get to the soldering iron, but an hour waiting at the airport (with my laptop) was used effectively. These are both just draft versions, neither the schematic nor the dimensions of the PCB have been checked. But it does look like (contrary to what I said above) an ISA card (at least a mini one) is possible with the freeware version of Eagle.

Bryce.

[keropi]

'nuff said

[PeterNC]

Wow! You are a true engineer Sir!

[keropi]

Bryce, did you design the card from scratch? even the ISA pins?

[Bryce]

Bryce, did you design the card from scratch? even the ISA pins?

Yeah, I had to, there isn't an ISA edge connector in the standard libraries. All the other bits are there though.

Bryce.

Btw: I gave KiCAD a quick try tonight... It's ok, but it's miles from Eagle as far as user friendliness and ease of use is concerned. If you are only doing relatively small PCBs I'd definitely recommend Eagle above KiCAD. I've downloaded DipTrace too, but I haven't had a chance to try it out.

[Geryon]

Will it be compatible with any ISA PC or XTs only?

[PeterNC]

The MIF-IPC works in 8086s / 8088s only. The MIF-IPC-A works in any ISA.

Additional background info: http://archive.is/wk3JR.

[Bryce]

I want to make a small 8bit ISA card of my own, I am stuck on the design though... I downloaded eagle/kicad/diptrace in hopes that there is an isa template or something but sadly I could not find one... any comments on what software to stick to and try to learn Bryce?

Is the card you're making a simple 8-bit ISA or do you need the full 16bit bus? If it's only 8-bit (like the MIF) then I can send you the edge component library I made. The 16-bit bus is too big for the freeware version of Eagle. Unfortunately it's only a simple model at the moment (cos' my plane arrived ), so if you needed the contacts to be gold-plated then I'd have to add tFinish / bFinish layers to specify this.

Bryce.

Update: I just gave DipTrace a go... What a nice program, very easy to use and a relatively good library. I could create a schematic and layout within a few minutes without having to refer to any tutorials. I'd put it on par with Eagle.

Update 2: Fixed up some dimensions (position of edge connector is now correct). Just need to check the position of the DB25 connector so that it fits a standard backplate with centred 25pin port.

[PeterNC]

Cool!

[keropi]

@Bryce

great work! I am jealous
the ISA card I want to make is 8bit , no need for 16bit connector! If you can share both eagle/diptrace libs I would be very grateful!!! I'll load it in both programs and see what sticks better to me TIA!

[Bryce]

I've only done the Eagle Library part so far. An 8-bit ISA card takes the freeware Eagle to it's limit (a square version of the card above is just about the max size the freeware version allows).
Here's the Eagle Library. It includes quite a few other parts - All parts I've needed for 8-bit projects that weren't in the standard library:

8255 PIO
628512 SRAM
Cartridge Edge Connector for Acorn Electron Plus 1
AD724 RGB to S-Video IC
AY-3-8910/2 in 24 and 28pin versions
50way Edge Socket for Amstrad expansions
Amstrad ACID IC
Cartridge Edge connector for Amstrad Plus
6845 - Video IC from Amstrad CPC range
FDC9266 - Floppy Controller IC
ISA-8bit Edge connector
MEA8000 - Voice Synth IC
MN4164 - DRAM IC
SPO256 - Voice Synth IC
µPD765 - Floppy Controller IC
WD1772 - Floppy Controller IC

Just unzip the file to the lbr folder in the Eagle folder and restart Eagle.
The backplate of the card would be to the right of the edge connector when viewing it in Eagle Layout. The white line coming from the right hand side of the connector marks the correct distance from the edge of the PCB.

Bryce.

[Bryce]

A quick photo update. Had some time for soldering this morning. The board is about 60% finished at this stage. Not looking quite as neat as it did a few days ago, but that's to be expected. Hopefully I'll get some more soldering time in soon and maybe have it finished and tested by the end of the week.

Bryce.

[PeterNC]

Looks amazing! I would not have been able to make it look so neat.

[keropi]

thanks for sharing the libs Bryce!!!
and the proto card looks great too

[PeterNC]

Bought another MPU-401 BOB this week (in DE ironically). And working on another one (in the US). That brings the total to 6.

This will provide better (empirical) evidence once we test the clone prototype.