MSM80C154S/83C154S/85C154HVS1444.7.5.4 Interrupt response time chart when an IE or IP manipulating instruction isexecuted after temporarily returning to the main routine from continuousinterrupt processingIf the next interrupt conditions are satisfied during execution of an interrupt processing routineand the interrupt terminating instruction RETI is then executed and followed by a return to themain routine where an instruction which manipulates the interrupt enable register (IE) orinterrupt priority register (IP) is executed, the MSM80C154S/MSM83C154S activates theinterrupt mask circuit in the next cycle following execution of the register manipulatinginstruction. And if interrupt conditions are met as a result of the re-interrupt mask, the interruptaddress is called in the next cycle. That is, if the instruction executed in the main routinemanipulates either IE or IP, the interrupt address is called after two instructions are executed.The time chart is shown in Figure 4-52.
