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sergey
January 30th, 2012, 03:11 PM
Hi,

I reordered and received Zeta SBC boards and components.

For more Zeta SBC documentation please refer to this page: http://n8vem-sbc.pbworks.com/w/page/44366173/Zeta%20SBC

Prices:
The Zeta PCB is $20, Z84C0020PEC (CMOS Z80 20 MHz CPU) - $5, FDC9266 (floppy disk controller IC) - $5, Toshiba TMP82C55 (Parallel Interface IC) - $4, and SST39SF040 flash (preprogrammed with BIOS, CP/M 2.2 and some utilities on ROM disk) - $4.

Shipping (one PCB each one of ICs, USPS First Class mail, no tracking) is $3 in US and $6 anywhere else.
If you're interested please send PayPal to skiselev:gmail/com (replace ':' with '@' and '/' with '.')

Thanks,
Sergey

Soupwizard
January 30th, 2012, 06:19 PM
I just received my second board, which is labeled v1.2 (the blue color is nice!). I have my first board (v1.1) started. In the PCB Version information (http://n8vem-sbc.pbworks.com/w/page/44366173/Zeta%20SBC#PCBVersions) you say the major change from 1.1 to 1.2 is that the power traces are 20% wider. Is that to correct a problem, or just because it was a good idea and you made the change since you were reordering the boards again?

Thanks,
Jeff

sergey
January 30th, 2012, 11:04 PM
I just received my second board, which is labeled v1.2 (the blue color is nice!). I have my first board (v1.1) started. In the PCB Version information (http://n8vem-sbc.pbworks.com/w/page/44366173/Zeta%20SBC#PCBVersions) you say the major change from 1.1 to 1.2 is that the power traces are 20% wider. Is that to correct a problem, or just because it was a good idea and you made the change since you were reordering the boards again?

Thanks,
Jeff

It is kind of both. First of all do try to improve boards between versions, and generally having wider power traces is a good idea. Also sometimes when using PPIDE with Transcend 40-pin IDE flash modules, I have a data corruption (only with these modules - all other IDE devices that I've tried worked properly). And I determined that it is related to power supply stability at the PPIDE (flash module receives power from PPIDE on pin 20), so perhaps making traces wider will resolve this problem.

Soupwizard
January 31st, 2012, 10:34 AM
It is kind of both. First of all do try to improve boards between versions, and generally having wider power traces is a good idea. Also sometimes when using PPIDE with Transcend 40-pin IDE flash modules, I have a data corruption (only with these modules - all other IDE devices that I've tried worked properly). And I determined that it is related to power supply stability at the PPIDE (flash module receives power from PPIDE on pin 20), so perhaps making traces wider will resolve this problem.

Ah so it won't affect my v1.1 board, as I'm planning on using it with floppy drives only. And even if I did want to use PPIDE, I could power the flash module off the external power supply if I wanted to be extra careful. Thanks for the info!

sergey
January 31st, 2012, 12:04 PM
Ah so it won't affect my v1.1 board, as I'm planning on using it with floppy drives only. And even if I did want to use PPIDE, I could power the flash module off the external power supply if I wanted to be extra careful. Thanks for the info!

Actually you can just connect additional ground and Vcc wires between PPIDE and the SBC. In my case, connecting additional ground wire helped (I've got it connected between mounting holes on both boards).