MMC card interface

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Re: MMC card interface

Post by KenLowe » Wed Apr 11, 2018 9:31 pm

I've made a slight modification to the wiring of the ribbon cable for my MicroSD reader, and I now no longer need to modify the MicroSD adaptor to get it working. I'm only using 6 wires, but with a bit of re-wiring at the IDC connector, I can get it all working and looking quite neat. The main trick was to double back one of the cores so that it was wired into two pins on the IDC connector. A bit fiddly to do, but the end result is quite nice:

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Re: MMC card interface

Post by DutchAcorn » Thu Apr 12, 2018 11:18 am

This looks clean, and there is no soldering required, but I've made a few of these and in my experience this configuration can give connection issues over time. The IDC connection is ok for a straight flat cable, but with twists and turns in the individual wires it is not so great. Imo soldering on the MMC interface side gives the most stable solution.

But as long as it works, it works! :D

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Re: MMC card interface

Post by Andy1979 » Sun May 20, 2018 3:29 pm

Another satisfied customer, finally got around to soldering up the cable for my Master Compact. Means that in the space of a weekend I've added an RS232 serial port, Wifi modem and 1gb of SD Card storage to it - not bad for a 30yr old machine :D .

Seems to work fine using *SRLOAD with MAMMFS 1.40. Tested it out with Higgys beeb.mmb file with all the games on it. Not all of the games work, but not sure if that's a Master Compact thing? (E-Type and Elite wouldn't run, and I'm getting graphical corruption in Zalaga)

Need to get MMFS burned to a ROM so that I can play Prince of Persia, as that needs all of the sideways RAM.
There's a small wire on the back of the reader bridging CS to ground.

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