Date   : Fri, 01 Apr 2016 21:45:33 +0100 (WET-DST)
From   : bbcmicro@... (Peter Coghlan)
Subject: Emulation

>
> In my emulation I'm scanning the keyboard and setting Bit 7 and Bit 0 of &FE4D
> to signify a keyboard IRQ request, which I think is correct, but this never
> gets serviced as bit zero of FE4D is low.
>

There is a contradiction here.  You say that you are setting Bit 0 of &FE4D
(which sounds right) but then you say bit zero of FE4D is low (which it
shouldn't be if you have just set it).

Regards,
Peter Coghlan.