Read MCU PIC16LF72 Program out from its flash memory and clone the whole firmware content from microcontroller PIC16LF72 to blank MCU which will provide the same functions;
The WDT has a nominal time-out period of 18 ms, (with no prescaler). If a longer time-out period is desired, a prescaler with a division ratio of up to 1:128 can be assigned to the WDT (under software control) by writing to the OPTION register.
Thus, a time-out period of a nominal 2.3 seconds can be realized. These periods vary with temperature, VDD and part-to- part process variations (see DC specs).
Under worst case conditions (VDD = Min., Temperature = Max., max. WDT prescaler), it may take several seconds before a WDT time-out occurs.
The CLRWDT instruction clears the WDT and the postscaler, if assigned to the WDT, and prevents it from timing out and generating a device RESET.
The SLEEP instruction resets the WDT and the postscaler, if assigned to the WDT. This gives the maximum SLEEP time before a WDT wake-up reset.
The TO, PD, and GPWUF bits in the STATUS register can be tested to determine if a RESET condition has been caused by a power-up condition, a MCLR or Watchdog Timer (WDT) reset.
A brown-out is a condition where device power (VDD) dips below its minimum value, but not to zero, and then recovers. The device should be reset in the event of a brown-out.
To reset PIC12C5XX devices when a brown-out occurs, external brown-out protection circuits may be built, This circuit will activate reset when VDD goes below Vz + 0.7V (where Vz = Zener voltage).
*Refer to Figure 8-7 and Table 11-1 for internal weak pull-up on MCLR.
This brown-out protection circuit employs Microchip Technology’s MCP809 microcontroller supervisor. The MCP8XX and MCP1XX family of supervisors provide push-pull and open collector outputs with both high and low active reset pins.
There are 7 different trip point selections to accomodate 5V and 3V systems.