Josh, Amazing job. Very nice. I'm a bit surprised the autorouter couldn't
do the board.
What a beast to do by hand.




On Wed, Jun 4, 2014 at 11:12 PM, Fabio Battaglia <[email protected]>
wrote:

> Hi Josh!
> I'd like 3 boards myself, when ready for production!
> Thanks,
> Fabio
> On Jun 5, 2014 7:55 AM, "Crusty OMO" <[email protected]> wrote:
>
>> Thanks Tom,
>>
>> I'll put you down for 2 boards and 3 LM323K's.  I'll try to make trip
>> across the boarder to ship them from the US side... let's see how the
>> timing works.
>>
>> Cheers,
>> Josh Bensadon
>>
>>
>> ------------------------------
>> Subject: Re: [N8VEM-S100:3966] ALTAIR/IMSAI 8080 CPU replacement board
>> From: [email protected]
>> Date: Wed, 4 Jun 2014 22:35:06 -0400
>> To: [email protected]
>>
>> I'll take two when your ready
>>
>>
>> Good work.
>>
>> ~~ _/) ~~~~ _/) ~~~~ _/) ~~~~ _/) ~~
>> Sent from my Phone
>>
>>
>> On Jun 4, 2014, at 10:19 PM, Crusty OMO <[email protected]> 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.
>>
>> <Pic.bmp>
>>
>>
>> Cheers,
>> Josh Bensadon
>>
>>
>>
>>
>> ------------------------------
>> From: [email protected]
>> To: [email protected]
>> 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.
>>
>> <IMG_1527.JPG>
>>
>>
>> Now entering Phase 2... building a PCB.
>>
>> Cheers,
>> Josh Bensadon
>>
>>
>> ------------------------------
>> From: [email protected]
>> To: [email protected]
>> 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] [mailto:[email protected]
>> <[email protected]>] *On Behalf Of *Crusty OMO
>> *Sent:* Tuesday, May 13, 2014 1:19 PM
>> *To:* [email protected]
>> *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].
>> 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.
>>
>> --
>> 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.
>>
>> --
>> 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.
>>
>>
>> --
>> 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.
>>
>> --
>> 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.
>>
>  --
> 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.
>



-- 
-------------------------------
Don Caprio [email protected]
http://www.uxpro.com
(925) 240-UNIX

-- 
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.

Reply via email to