Setting the extra pins for the BS2p40???
I just got a BS2p40 and I'm trying to set the extra pins.· I've set 0-15 to components, and 16 is the known serialIO.· So what are the other PINs I can set components to?
Thanks,
Justin
Thanks,
Justin
Comments
Is the concept similar to the dual registers of the old Z80 processor?
--Bill
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You are what you write.
In a way, it's similar. It's a way of compatibly expanding an existing instruction set by adding special instructions to select one of two banks of registers or I/O pins or whatever. All the other instructions work the way they used to, but they work on one set of registers or I/O pins at a time.
Mike
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·· The shadow registers on the Z80 could be swapped with an alternate set.· This was usually used in interrupt routines to save having to push everything onto the stack.· This had no effect on the I/O pins or registers related to them.
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·· On the BS2p40 when you use MAIN, AUXIO or IOTERM you are changing which bank of I/O pins that subsequent I/O related instructions affect.· I hope this helps.· Take care.
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Chris Savage
Parallax Tech Support
Yes, that helps a lot. Thanks once again.
--Bill
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You are what you write.