Datasheet

© 2008 Microchip Technology Inc. DS41249E-page 107
PIC16F785/HV785
15.0 SPECIAL FEATURES OF THE
CPU
The PIC16F785/HV785 has a host of features intended
to maximize system reliability, minimize cost through
elimination of external components, provide power sav-
ing features and offer code protection.
These features are:
• Reset:
- Power-on Reset (POR)
- Power-up Timer (PWRT)
- Oscillator Start-up Timer (OST)
- Brown-out Reset (BOR)
• Interrupts
• Watchdog Timer (WDT)
• Oscillator selection
• Sleep
• Code protection
• ID Locations
• In-Circuit Serial Programming™ (ICSP™)
The PIC16F785/HV785 has two timers that offer
necessary delays on power-up. One is the Oscillator
Start-up Timer (OST), intended to keep the chip in
Reset until the crystal oscillator is stable. The other is
the Power-up Timer (PWRT), which provides a fixed
delay of 64 ms (nominal) on power-up only, designed to
keep the part in Reset while the power supply stabi-
lizes. There is also circuitry to reset the device if a
brown-out occurs, which can use the Power-up Timer
to provide at least a 64 ms Reset. With these three
functions on-chip, most applications need no external
Reset circuitry.
The Sleep mode is designed to offer a very low-current
Power-down mode. The user can wake-up from Sleep
through an external Reset, Watchdog Timer Wake-up
or interrupt.
Several oscillator options are also made available to
allow the part to fit the application. The INTOSC option
saves system cost, while the LP crystal option saves
power. A set of configuration bits are used to select
various options (see Register 15.2).
15.1 Configuration Bits
The configuration bits can be programmed (read as
‘0’), or left unprogrammed (read as ‘1’) to select various
device configurations as shown in Register 15.2.
These bits are mapped in program memory location
2007h.
Note: Address 2007h is beyond the user program
memory space. It belongs to the special
configuration memory space (2000h-
3FFFh), which can be accessed only during
programming. See “PIC16F785/HV785
Memory Programming Specification”
(DS41237) for more information.