If the comparisons are false, the LSI53C810A fetches the next instruction from the address pointed to by the DMA SCRIPTS Pointer (DSP) register and the instruction pointer is not modified.

Return Instruction

The LSI53C810A can do a true/false comparison of the ALU carry bit, or compare the phase and/or data as defined by the Phase Compare, Data Compare, and True/False bit fields.

If the comparisons are true, then it loads the DMA SCRIPTS Pointer (DSP) register with the contents of the DMA SCRIPTS Pointer Save (DSPS) register. That address value becomes the address of the next instruction.

When a Return instruction is executed, the value stored in the Temporary (TEMP) register is returned to the DMA SCRIPTS Pointer (DSP) register. The LSI53C810A does not check to see whether the Call instruction has already been executed. It does not generate an interrupt if a Return instruction is executed without previously executing a Call instruction.

Transfer Control Instructions

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LSI 53C810A technical manual Return Instruction