The P112 is a stand-alone 8-bit CPU board. Typically running CP/M (tm) or a similar operating system, it provides a Z80182 (Z-80 upgrade) CPU with up to 1MB of memory, serial, parallel and diskette IO, and realtime clock, in a 3.5-inch drive form factor. Powered solely from 5V, it draws 150mA (nominal: not including disk drives) with a 16MHz CPU clock. Clock speeds up to 24.576MHz are possible.
The P112 board was last available new in 1996 by Dave Brooks. In late 2004 on the Usenet Newsgroup comp.os.cpm, talk about making another run of P112 boards was discussed. I decided to step forward. With Dave Brooks blessing and the assistance of others, new boards were fabricated. Those boards too are gone. Still people want P112 kits. This Kickstarter project is intended to finance the purchase of boards and components for 150 kits. The magic number is 72. I need 72 people to put money down for one to make it go. If more than 150 people want kits, that's fine. I'll make more.
What's this thing good for? It's for you classic-computer buffs who enjoy playing around with CP/M and similar operating systems. It's for microcontroller tinkerers who want an inexpensive Z180 platform.
The main page for the P112 is at http://661.org/p112/. From there you can get the complete user's manual, software, see pictures, and learn much more.
The P112 boards will be fabricated by Sunstone Circuits (http://www.sunstone.com/) in Mulino, Oregon. The surface mount components (CPU and SuperIO) will be mounted by Screaming Circuits (http://www.screamingcircuits.com/) of Canby, Oregon. The surface-mount parts will be acquired from the manufacturers, from a chip broker, and from Mouser (http://www.mouser.com/). I will also include two CDs. One contains complete documentation and an archive of CP/M software and files collected by Rlee Peters and another CD which is a copy of the freely-redistributable Walnut Creek CP/M CD.
Risks and challenges
I produced a run of P112 kits a couple years ago and it went very smoothly. Back then I had assistance from a friend to get the financing started. This time that sort of financing wasn't on the table. I decided to continue using a US-based board fabber and stuffer because I like the reassurance of a company that's relatively close. I know people within driving distance of the place who can help out with problems if they arise. Putting the parts into kits is simpler this time around because I'm not sorting thousands of tiny parts: just boards, boot ROMS, CDs, and serial port pigtails.Learn about accountability on Kickstarter
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