A simple startup question

[teilhardo]

Hi Bruce,
Thank you very much for the informative descriptions. Unfortunately, after programming word for word into cd lite and then programming the PIC, it still ceases to work. I attached 3VDC to VDD, ground to VSS and then using an ohm meter, tested the voltage at RB0 and RA0, but got 0V everywhere I tried. Is it possible that 2.55V (the measured series voltage in the batteries) is to low?
Thanks,
Tei

[Bruce]

Minimum operating voltage for the non LF parts is 3V. Look in the data sheet under Electrical Specifications.

Running at lower voltages, you'll normally need to turn off brown out detection, and power up timer.

These are config fuse settings. You can change them by adding them to your config directive line, or using your programmers software.

BODEN_OFF disables brown out detection allowing you to run the PIC at minimum voltage. PWRTE_OFF disables the power up timer.

Change your config fuse directive line to something like this if you're not disabling these with your programmer before burn time.

@ DEVICE MCLR_OFF,LVP_OFF,INTRC_OSC,WDT_OFF,BODEN_OFF,PWRTE _OFF

You can save yourself a lot of time & aggravation by just getting a cheapo regulated +5VDC power supply. If you're just getting started, it's a lot easier working with 5V than a low-power design.

[teilhardo]

No wonder it didn't work. I'll run down to radioshack and see what I can get