RCM - RETRO COMPUTER MUSEUM

GENERAL => HARDWARE/SYSTEMS DISCUSSION => Topic started by: John Ferguson on April 02, 2018, 12:55:35 PM

Title: Micro Power Ltd Rom board
Post by: John Ferguson on April 02, 2018, 12:55:35 PM
I wonder whether anyone knows how to select each Rom.

Help would be appreciated. It was inside an Acorn Atom.

John
Title: Re: Micro Power Ltd Rom board
Post by: DarrenColes on April 03, 2018, 03:52:15 PM
is there anything on the underside?

i'm guessing the board plugs into the rom socket on the motherboard underneath, since there aren't enough wires connected on the black connector to provide the data and address lines needed to address the 4k rom

i'd guess the connector is just there to pull the address lines and data lines needed to do the bank switching. it might be possible to make a guess at the address used to trigger the bank switching if we knew which pins were connected to which wires and what the pinout is of the socket that it connects to.

Darren

Title: Re: Micro Power Ltd Rom board
Post by: John Ferguson on April 03, 2018, 07:20:56 PM
Hi Darren

Thank you for responding to my posting.

Since then a person on www.stardot.org.uk has given me all the information I need. I posted here and there not knowing who could help.

The roms can be accessed by ?#9C000=0, ?#9D000=0, ?#9E000=0, and ?#9F000=0

John
Title: Re: Micro Power Ltd Rom board
Post by: DarrenColes on April 06, 2018, 02:16:37 PM
good to here you got it sorted. saves me having to try and figure it out from the pinouts :-)