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Re: SCC and Z80/8086 monitor

Bob,

I got my Z85C30 from Mouser. Make sure you get at least the 10 MHz one. I got mine a couple of months ago and am about to order the 16 MHz version. The rated speed (at least according to the SCC family data) not only characterizes the interface speed but also characterizes the serial clock oscillator maximum frequency. The higher that clock is the more options you have especially at higher serial speeds.

Do not substitute the similar but incompatible members of the SCC family for the Z85C30.

Rich Leary.

On Thursday, November 13, 2014 4:03:43 PM UTC-7, Bob Bell wrote:
Based on some favorable reviews, and in need of another serial port and the lure of a really high-speed USB connection, I acquired one version 03 Serial I/O board.  Then I set out to locate the parts.  8255 located in my parts bin.  But no Z8530 although I have just about everything else.  So I searched Jameco and a couple other suppliers, but it seems no one has the Z8530.  Two questions: 1) can the Z8531 be used in place of the Z8530 (seems like it lacks the synchronous operation), and 2) has anyone bought Z8530 recently, and from where?

Thanks for your help!

Bob B


On Friday, November 7, 2014 10:33:33 PM UTC-5, AltairManRich wrote:
All —

I gave up on the MSDOS board/8086 CPU for a while and assembled the Serial IO board (V2) that I had in stock and tried to get it working with the Z80 board (V1) and the SMB (V1) that I have using the standard-issue monitor program (v4.8). I don’t usually use the SMB but it seems to be needed for the IOBYTE to force console I/O to the SCC. Like with the problems I had with the MSDOS board, this configuration also exhibits “input anomalies”. In this case, I see only output — no input. I can definitely “see” characters coming through the interface (using my protocol analyzer), but nothing on the screen.

I wrote a small loop-back program to run under my alternative monitor program (one based on Dave Dunfield’s MON85) with the Z80 board and the Serial I/O board. The SIO board passes the loopback. 

So, there must be a configuration or other issue with the v4.8 monitor that I’m not seeing. Does anyone have a working combination of boards using the SIO and N8-S100 Monitor and can tell me how to force the console input and output to the SIO without needing the SMB? Maybe I’m missing a compilation switch somewhere.

Thanks!

Rich

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Rich Cini
Collector of Classic Computers
Build Master and lead engineer, Altair32 Emulator