In order to permit a free intermix of Zorro II and Zorro III cycles, the bus control logic is capable of making intelligent decisions when spacing bus cycles. In somc cases, a Zorro II cycle has some component that would naturally extend into a following cycle. The cycle spacing logic detects such a condition, and refuses to start a new cycle until the current one is complete, even if this extends beyond the defined bounds of a Zorro II cycle. For Zorro II PICs that really follow the Zorro II specifications, this should have no effect. However, any Zorro II PIC that holds signals much beyond the end of a cycle, especially critical signals like /SLAVE and /DTACK , will likely incur additional wait states on the Zorro III bus. This is not intended as a license for making sloppy expansion card designs, just an acknowledgement that some Zorro II devices may cause a conflict with the faster Zorro III bus timings . The best approach is to make them work, even with a possible performance penalty.
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