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jellis00
- 14th June 2009, 20:03
The data sheet for the 16F690 says that one of the things to do to minimize power during SLEEP mode is to disable CVREF. I looked at all the registers and can't find where I can disable CVREF. Can anyone tell me how to do this?:(

Melanie
- 14th June 2009, 21:34
CV1REN, CV2REN and VP6EN bits of the VRCON Register.

See 8.10.1 and Register Table 8-5.

jellis00
- 14th June 2009, 23:04
Thanks so much Melanie. As much as I searched the data sheet I somehow missed this.
I have a similar question regarding T0CKI. Data sheet sheet says to minimize power during SLEEP the T0CKI pin should be at Vdd or Vss. Since T0CKI is multiplexed win pin RA2, I have been searching datasheet looking at how to select T0CKI and only register I see it referenced in is OPTION_REG bits 4 and 5. Don't see T0CKI mentioned in any other registers.
If I set bits 4 and 5 to 1 in OPTION_REG does that select T0CKI on pin RA2??? If that is the way to make the selection, I presume I would then just make the PBASIC statement PortA.2 = 0 to set it to Vdd for minimum power consumption????

Melanie
- 15th June 2009, 12:44
Tricky... simply setting the pin to Output could clash with whatever external circuitry you're using to drive the Clock. Obviously what Microchip wants you to do is not toggle the pin, that will naturally stop the PICs internals from doing their thing. If you have a pull-up on that pin, pulling it to 0v will start drawing current... a little more thought is needed as to what how and where before a decision is made on this one.