EM78P259N/260N
8-Bit Microprocessor with OTP ROM
6.10.3 Using a Comparator as an Operation Amplifier
The comparator can be used as an operation amplifier if a feedback resistor is externally connected from the input to the output. In this case, the Schmitt trigger can be disabled for power saving purposes, by setting Bit 4, Bit 3<COS1, COS0> of the IOC80 register to <1,1>. See table under Section 6.2.4, IOC80 (Comparator and TCCA Control Registers) for Comparator/OP select bits function description.
NOTE
Under Operation Amplifier:
■The CMPIE (IOCE0.4), CMPWE (RE.2), and CMPIF (RE.4) bits are invalid.
■The comparator interrupt is invalid.
■The comparator
6.10.4 Comparator Interrupt
CMPIE (IOCE0.4) must be enabled for the “ENI” instruction to take effect
Interrupt is triggered whenever a change occurs on the comparator output pin
The actual change on the pin can be determined by reading the Bit CMPOUT, IOC80<5>.
CMPIF (RE.4), the comparator interrupt flag, can only be cleared by software
6.10.5 Wake-up from Sleep Mode
If the CMPWE bit of the RE register is set to “1,” the comparator remains active and the interrupt remains functional, even under Sleep mode.
If a mismatch occurs, the change will wake up the device from Sleep mode.
The power consumption should be taken into consideration for the benefit of energy conservation.
If the function is unemployed during Sleep mode, turn off the comparator before entering into sleep mode.
The Comparator is considered completed as determined by:
1.COS1 and COS0 bits of IOC80 register setting selects Comparator.
2.CMPIF bit of RE register is set to “1”.
3.CMPWE bit of RE register is set to “1”.
4.
5.
6.Enters into Interrupt vector (address 0x00F), if CMPIE bit of IOCE0 is enabled and the “ENI” instruction is executed.
60 • | Product Specification (V1.2) 05.18.2007 |
| (This specification is subject to change without further notice) |
