Re: EI/RETI (was Re: Accessing disk with disabled interrupts)

[Ricardo Bittencourt Vidigal Leitao]

On Thu, 22 Jul 1999, MkII wrote:

> But it has a reason I forgot. What's the actual effect of RETI? 

        RETI is the same thing as RET, only with a different opcode.

        Some Z80-based devices can detect the opcode of RETI when it's on
the data bus, and by doing this they can know when it's time to issue
another interrupt. This feature is not used in the MSX computer.

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Ricardo Bittencourt               http://www.lsi.usp.br/~ricardo
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