On Tue, Nov 29, 2016 at 1:43 AM, Al Kossow <a...@bitsavers.org> wrote: > I bought a rev 1 with proms and a print server from dca on ebay today to dump > > http://www.ebay.com/itm/192014611480
That is the board I was thinking of. > http://www.ebay.com/itm/262721065197 > > On 11/28/16 5:33 PM, Eric Smith wrote: >> On Sun, Nov 27, 2016 at 8:12 AM, Al Kossow <a...@bitsavers.org> wrote: >> >>> IRMA card >>> >> >> I'd forgotten about that. The later ones designed the 8X305 out. It's >> interesting in that the firmware gets loaded into RAM, rather than running >> for PROM. >> > My guess is that EPROMs of that time were not fast enough for the 8X305 to run flat out. Bipolar PROMs were too expensive in the capacity needed. So they copied the code into (fast enough) SRAM at startup. -tony