UPD75208 NEC, UPD75208 Datasheet - Page 23

• Manufacturer Part Number: UPD75208
• Description: 4-BIT SINGLE-CHIP MICROCOMPUTER
• Manufacturer: NEC

5.9
on reset signal is generated. (See Fig. 8-1 Reset Signal Generator)
manipulation instructions (SKT, SKF, SKTCLR) or cleared (CLR1).
Note
6. INTERRUPT FUNCTIONS
The power-on flag (PONF) is automatically set (1) when the power-on reset circuit is activated and the power-
The PONF is mapped at bit 0 of address FD1H in the data memory space and can be tested by the memory bit
The PD75208 has eight types of interrupt sources and can generate multiple interrupts with priority order.
It is also equipped with two types of test sources. INT2 is an edge detected testable input.
The PD75208 interrupt control circuit has the following functions:
• Hardware-controller vectored interrupt function which can control interrupt acknowledge with the interrupt
• Function of setting any interrupt start address.
• Multiple interrupt function which can specify priority order with the interrupt priority select register (IPS).
• Interrupt request flag (IRQ
• Standby mode release function. (Interrupt to be released by interrupt enable flag can be selected.)
enable flag (IE
POWER-ON FLAG (MASK OPTION)
The PONF cannot be set by SET1 instruction.
) and the interrupt master enable flag (IME).
) test function. (Interrupt generation can be checked by software.)
PD75208
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