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 [ 1 post ] 
 8080 SBC with tiny floating point Basic 
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Joined: Wed Jan 09, 2013 6:54 pm
Posts: 1644
Dave Banks was given this 1978ish 8080 development system, and has been trying to get it working and explore what it can do. It has an 8080 (needs ±12V as well as 5V) 4k of ROM implemented with 4 chips and 1k of RAM implemented with 8 chips. There's a UART, and Dave was able to talk to the Basic - a 4k Basic with floating point! Dave's dumped the ROMs and I was able to run the Basic interpreter using Óscar Toledo Gutiérrez' wonderful IOCCC-winning 8080 emulator - itself smaller than 4k. The adventure continues - the machine is sickly and the ROMs only work with lots of freezer spray.

Others have turned up the original monitor for the machine - the tiny Basic has a peek and poke facility and a USR command but there's no monitor.

BTW the machine has a video output card, which is serial-connected using another UART (1200bps) and which has just 1k of 6-bit wide memory and a character generator ROM for an Apple I or II - apparently a standard part, offering just 64 characters in a 5x7 matrix.

For details of the adventure, see http://stardot.org.uk/forums/viewtopic.php?f=3&t=9821

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(Reposted from here - be sure to keep an eye on Retro Computing over at gplus)


Mon Jul 20, 2015 10:08 am
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