I have an extra of Josh's 8080A Rev 0 CPU board if anyone is interested... $20 + $4 shipping
tom... On Thu, Nov 20, 2014 at 8:20 AM, Richard Cini <[email protected]> wrote: > I don't know if there's room, but you could use the output on port EFh for > 8 LEDs for diagnostic progress. > > Sent from my iPhone > > On Nov 20, 2014, at 11:14 AM, John Monahan <[email protected]> wrote: > > Can we have the sense switch (IOBYTE) pegged to 0EFH to make life simple. > Is used a lot in our earlier software. > > John > > > > > > *From:* [email protected] [mailto:[email protected] > <[email protected]>] *On Behalf Of *Richard Cini > *Sent:* Thursday, November 20, 2014 7:33 AM > *To:* [email protected] > *Subject:* Re: [N8VEM-S100:5635] Re: 8080a board > > > > All good ideas, especially the 8085 and the sense switch input. I wish the > msdos board had a sense switch input. > > Sent from my iPhone > > > On Nov 20, 2014, at 10:09 AM, Tom Lafleur <[email protected]> wrote: > > Some notes for Ver one... To gain some room on the board.... > > > > As suggested before.... > > > > Use only 4 wire rs232 with max232a/tr202, removing need for +-12v ( 3 to 4 > chip saving) > > Move to 8085, no need for +12 or -5v, less support chip needed... ( ~2 > chip saving) > > > > Make board stand alone, no other boards needed to make it run... ( plus 1 > chip) > > Fix upper address and data lines to bus issues . (Plus 2 chips) > > > > New ideas... > > > > Replace 8212's with 74als logic (~ 3 chip saving) > > > > Replace ram chips with one larger chip, (wasting part of the chip to save > room if needed) 64k x 8 or larger like an as6c4008 with a poor man's mmu if > their room on board...(use output port?) like zeta board.... (~ plus 1 to 2 > chip saving) > > > > If room, allow room for a dip switch with pull-ups on input port.... (~ > plus 1 chip) > > > > > > Just my ideas from building the board.... > > > > > > > > > > > > i~~ _/) ~~~~ _/) ~~~~ _/) ~~~~ _/) ~~i > > > > Tom Lafleur > > > > > On Nov 19, 2014, at 8:00 PM, Crusty OMO <[email protected]> wrote: > > Opps, thanks for letting me know... I guess it's a cut n paste error or > just an over sight. > > > ------------------------------ > > Date: Wed, 19 Nov 2014 16:34:41 -0800 > Subject: 8080a board > From: [email protected] > To: [email protected] > > fyi... > > > It appears that UART1 at A5 is connected to COM1 port, P1/P2 on the > board, but the schematic say its connected to P3/P4 > > > -- > > > ~~ _/) ~~~~ _/) ~~~~ _/) ~~~~ _/) ~~ > > Tom Lafleur > > -- > 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. > -- ~~ _/) ~~~~ _/) ~~~~ _/) ~~~~ _/) ~~ Tom Lafleur -- 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.
