[MSX] MSX-Audio BIOS upgrade for Music Module

Oscar Centelles kaneda at filnet.es
Wed May 11 23:49:23 CEST 2005


> Hi Richard,
>
> > I have a quick question - the diagram online still shows 27C256 pin 20
> > connected to 74LS139 pin 12 and 6164 pin 20 connected to 74LS139 pin 11.
> > Should these two signals be swapped? JP Grobler mentions he swapped
them;
> > I think in order to get the memory map above they do need to be swapped.
>
> Yes, you're right. The correct conections are:
>
> 74LS139
> pin-12 -> 6164,pin-20
> pin-13 -> 27c256,pin-20

Hi,

Are these connections ok? What 74LS139 pins must be swapped? ¿11<->12 or
12<->13? I am a bit confused.

Thank you!!

Greetings,

Oscar





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