FW: S-100 Utility board KiCAD files uploaded to wiki

Subject: FW: S-100 Utility board KiCAD files uploaded to wiki

From: "Andrew Lynch" <LYN...@YAHOO.COM>

Date: Sun, 12 Oct 2014 15:50:51 -0400

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I’ll forward to the group and see if anyone wants to adopt this project.

The attached ZIP file is on the wiki in the S-100 Utility folder

Thanks!

Andrew Lynch

From: Neil Breeden [mailto:nbre...@me.com]
Sent: Sunday, October 12, 2014 12:06 PM
To: Andrew Lynch
Cc: 'Todd Goodman'; mon...@vitasoft.org
Subject: Re: S-100 Utility board KiCAD files uploaded to wiki

Guys,

I've been able to verify the following work:

- Port decoding for the UART

- The UART

- The 27C256 EPROM
- The 32K RAM at U27

- I can toggle bits on the Printer port

I have a version of my BASIC in ROM that works on the board using the on-board EPROM, RAM and UART for console I/O.

Other functions such as the RTC, Extra RAM (U29 and U18) and MSX ports have not been verified.

Issues with the board (Version 01)

- MREQ Issue (see attached) - Need to replace NAND with NOR gates

- I'm not convinced that the RESET circuit works reliability

Neil Breeden

nbre...@me.com

On Oct 12, 2014, at 06:23 AM, Andrew Lynch <LYN...@YAHOO.COM> wrote:

Hi Todd

I uploaded the S-100 Utility board KiCAD files. It occurred to me this morning they had not been uploaded previously.

http://n8vem-sbc.pbworks.com/w/browse/#view=ViewFolder&param=S-100%20Utility

Neil had debugged the board and it was probably nearly complete.

It is probably close enough for a small batch of PCBs to hammer out the remaining issues.

The S-100 Utility board along with an S-100 VDP and S-100 Z80 CPU board form a three board core full hardware MSX2 compatible system.

Good luck! Thanks and have a nice day!

Andrew Lynch