Epson RX-8564LC Page −, ETM12E-01, 13.4. /INT "L" Interrupt Output When Interrupt Function Operates

RX − 8564 LC

13.4. /INT "L" Interrupt Output When Interrupt Function Operates

1) Setting interrupt events to occur in response to /INT "L" interrupt output

The /INT interrupt output pin is shared as the output pin for two kinds of interrupt events: events related to the fixed-cycle timer interrupt function and events related to the alarm interrupt function.

When an interrupt occurs (when /INT is at low level ("L")), read the TF and AF flags to determine which type of interrupt event occurred (which flag value changed to "1").

2) How to prevent /INT pin from going to low level ("L")

To prevent the /INT pin from going to low level ("L"), clear all TIE and AIE bits to zero.

To detect when an interrupt event has occurred without having to set the /INT pin to low level, monitor the TF and AF flag bit values to see if the target interrupt event has occurred (i.e., to see if either flag bit value changes from "0" to "1").

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