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Is there any way to read current Interrupt Mode in Z80 machine code?

Is there any way to read current Interrupt Mode in Z80 machine code? By the CPU alone: No. There is no way to read out the content of the interrupt mode flip-flops. Also, why should it? Interrupt ...
Raffzahn's user avatar
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26 votes
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Is there any way to read current Interrupt Mode in Z80 machine code?

The Mirage Microdriver (a snapshot device for the ZX Spectrum) needs to record the current interrupt mode when a snapshot is made. It does this by setting I to 80h and storing the address of an ...
john_e's user avatar
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3 votes
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What was the 6502's reset behaviour when the RDY pin was low

From the "MCS6500 Microcomputer Family Hardware Manual (January 1976)" (p. 37) The RDY input delays execution of any cycle during which the RDY line is pulled low. This line should change ...
masswerk's user avatar
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