Toshiba TC9314F Manual

TC9314F2003-07-0344Interrupt FunctionINTR1 and INTR2 are the input pins for the external interrupts. These pins can also be used for remotecontrol signal input and tape running detection input. The pins can also be set as general-purpose input portsby software.1. Interrupt FunctionThe interrupt function consists of two external interrupt sources: interrupt 1 and interrupt 2. Thefunction supports prioritized multiple interrupts. The interrupt circuit is set using an internal port.Interrupts are received based on the signals input to the corresponding pins (INTR1, INTR2).Interrupt 1 is suitable for use as the remote control interrupt. If the interrupt source input is at highlevel (with the interrupt signal set for positive logic input) for longer than the time set by the countercircuit (0.3~12.5 ms), the signal is recognized as an interrupt. Interrupt 2 is suitable for detecting the endof tape in a cassette deck. The interrupt function begins measuring on a rising edge (with the interruptsignal set for positive logic input). If no other rising edge occurs within the time set by positive logic input).If no other rising edge occurs within the time set by the counter circuit (0.1~6.2 s), the signal isrecognized as an interrupt.If the counter setting data are “01H” for either interrupt 1 or interrupt 2, for a pulse of 120 μs or longerthe interrupt can be received.The input pins are Schmitt inputs. Moreover, because an internal noise rejection circuit is provided,noise pulses of less than 80~120 μs are not detected. The input logic is controlled by an internal portsetting to suit various input signals.ExternalInterrupt Input Pin Interrupt Signal Detection Width EnableCondition Priority EntryAddressINTR1(interrupt 1)Minimum detection width 120 μsTimer interrupt time 0.3~12.5 msINTE1 = 1IEF1 = 1 1 Address 1INTR2(interrupt 2)• Schmitt input• Input logic levelcontrol Minimum detection width 120 μsTimer interrupt time 0.1~6.2 sINTE2 = 1IEF2 = 1 2 Address 2