Hi Josh, The board looks great. You can put me down for one. Leon Byles
On Thursday, June 5, 2014 12:19:34 PM UTC+10, Crustyomo wrote: > Hi Guys, > > Well I'm finally done laying out this board. The autorouter only produced > swiss cheese with over 900 via's. It looked terrible! > Anyway, I scrapped everything the autorouter did initially, and proceeded > to layout the traces manually. Once I got what I thought was all the hard > parts done, I let the autorouter have another go at it. Again it did not > work out so well and it was unable to complete the board, so I proceeded to > undo it's changes and/or improve it's routing manually. I squeezed those > traces in there tight, any tighter and they'll be popping off the board. > Anyway, I'm working on the silkscreen layer and ready to do a run. > Here's a picture of the board layout.... > You can see the serial port connections on the top left, SD card to the > right of the 27C256 EPROM, parallel ports next to that and the ALTAIR and > IMSAI front panel connectors. There are also a few jumpers around the > board to configure for CPU or Peripheral board only and ALTAIR/IMSAI mode. > Firmware for the board will be my next project, but I have to make > preparations for VCF-MW my priority. Dave Ruske and I will be doing a > COSMAC 1802 exhibit there in September. > > > > Cheers, > Josh Bensadon > > > > > ------------------------------ > From: [email protected] <javascript:> > To: [email protected] <javascript:> > Subject: RE: [N8VEM-S100:3711] ALTAIR/IMSAI 8080 CPU replacement board > Date: Sun, 18 May 2014 00:57:20 +0000 > > Hi Guys, > > Well, this project has just reached a milestone. The hardware is tested > and working. I had some rewiring to do to make it work for the ALTAIR, I > thought the ALTAIR and IMSAI front panels were (near) identical, but they > are not. > There are some jumpers on the board to configure between ALTAIR and IMSAI. > > Here's a picture of my debugging and testing setup. The board is being > tested in the ALTAIR. > > > > Now entering Phase 2... building a PCB. > > Cheers, > Josh Bensadon > > > ------------------------------ > From: [email protected] <javascript:> > To: [email protected] <javascript:> > Subject: RE: [N8VEM-S100:3666] ALTAIR/IMSAI 8080 CPU replacement board > Date: Tue, 13 May 2014 13:56:05 -0700 > > Very nice Josh! > > John > > > > *From:* [email protected] <javascript:> [mailto: > [email protected] <javascript:>] *On Behalf Of *Crusty OMO > *Sent:* Tuesday, May 13, 2014 1:19 PM > *To:* [email protected] <javascript:> > *Subject:* RE: [N8VEM-S100:3664] ALTAIR/IMSAI 8080 CPU replacement board > > > > Hi Group, > > Well, I'm cooking up this board at the moment. I have all the hardware > figured out to run like the original CPU boards. > I need to do a little more testing of the hardware, then I'll proceed to > building the boards. > The Memory, I/O, UARTs and SPI interface to the SD card appear to all be > working. > 8K chunks of memory can become either ROM, RAM or mapped off the board. > > CPU: 8080A > UARTS: 2x 8250 > RAM: 2x 32K > ROM: 32K > I/O: 8 input, 6 output pins > SPI to SD Card interface > ALTAIR & IMSAI Front Panel Connectors. > > Where ROM is selected in a block it overlaps the RAM on reads, but writes > go through to RAM. > The ROM can then be disabled and reads will come from the RAM at that > location. > The firmware is copying itself to RAM then switching off the ROM. > The CPU can be deselected with jumpers and the board will work as RAM/ROM > and I/O for another CPU on the bus. > > Pictures attached. Yellow-Data, Brown-Address, Blue-I/O, > Green-Control/Status & everything else. > > Regards, > Josh Bensadon > > > > > -- > You received this message because you are subscribed to the Google Groups > "N8VEM-S100" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > For more options, visit https://groups.google.com/d/optout. > > -- > You received this message because you are subscribed to the Google Groups > "N8VEM-S100" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > For more options, visit https://groups.google.com/d/optout. > > -- > You received this message because you are subscribed to the Google Groups > "N8VEM-S100" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "N8VEM-S100" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
