Re: FPGA/CPLD different approach

From: Istvan Hegedus <hegedusis_at_t-online.hu>
Date: Wed, 4 Sep 2013 14:25:09 +0200
Message-ID: <FC700267A6524CEA82B37978B521F1F0@emea.hpqcorp.net>
Hi,

I would say if the PCB is slightly larger than the original DIP that is not a problem although e.g. in case of the plus 4 you could not use that for TED replacement due to the space in the shield. For me the inside is much more important, to have as accurate emulation as possible.
The emulation could be used to build a whole system in FPGA (like FPGA64).
Hege 
From: Bil Herd 
Sent: Tuesday, September 03, 2013 3:15 PM
To: cbm-hackers@musoftware.de 
Subject: RE: FPGA/CPLD different approach

I did a quick fitting on some opencores and found that the PIO’s and support chips probably fir in the CPLD’s and that the processors probably didn’t.



I have a question for anyone that is interested in using FPGA/CPLD emulated parts: How important is it that the PCB of a drop in replacement stay strictly in the foot print of a 40/48 pin chip or is the PCB okay to be wider than .6” once its .3-.4” above the socket it’s inserted into?



Bil



From: owner-cbm-hackers@musoftware.de [mailto:owner-cbm-hackers@musoftware.de] On Behalf Of Ed Spittles
Sent: Tuesday, August 27, 2013 4:13 PM
To: cbm-hackers@musoftware.de
Subject: Re: FPGA/CPLD different approach



For some purposes OHO's GOP board might be a better fit than the GODIL - it's smaller, got fewer pins, but has a 512kByte SRAM on board..

http://www.trenz-electronic.de/products/fpga-boards/oho-elektronik.html

http://shop.trenz-electronic.de/catalog/default.php?cPath=1_48_137



(For simple designs there are CPLD variations, but as noted that's not big enough for a 6502-like CPU, or for ROM or RAM.)



As noted elsewhere, these boards have 5V level converters, crystals, and on-board EEPROM for configuration.



Cheers

Ed





On 27 August 2013 11:34, Ingo Korb <ml@akana.de> wrote:

Bil Herd <bherd@mercury-cg.com> writes:

> I have gone through some test fitting but haven't really checked out
> GODIL, for instance can they program the VCC and Ground pins or do
> they have to physically configure?

They can be freely configured using jumpers, but as Didier noted the
pinning of those headers is a bit weird. IIRC the DIL pin alternates
between the left and right side of the header and the other pin
alternates between 5V and GND for each row, so you can select GND and 5V
for any DIL pin by setting the jumper either horizontally or
vertically.


> I suspect that to keep the cost
> down that the PCB might be wider than the .6" DIP but didn’t yet
> research if that’s a show stopper.

It's much wider and longer - the board is 33.5 mm x 74.3 mm, the DIL
interface at the bottom appears to be centered. The overall height
including the DIL pins is ~20 mm.

-ik


       Message was sent through the cbm-hackers mailing list





       Message was sent through the cbm-hackers mailing list
Received on 2013-09-04 13:00:08

Archive generated by hypermail 2.2.0.