[A83] im 2
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[A83] im 2
According to the cpu manual, when you use interrupt mode 2, you should create a pointer table somewhere in memory, then put in the I reg the most significant byte. When an interrupt happens the Z80 takes the I register and the interrupting device provides the lower 8 bits. Then it jumps to the pointer stored at the address that is formed. The manual also says that the lowest bit provided should always be 0 to create even numbers, because pointers are 16 bit and therefore take 2 bytes. For now I've discovered that this isn't the case on the 83-. The interrupting device seems to generate an 8 bit numbers (not 7). But is this also on the 83+(SE)?
--Tijl Coosemans
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