PIC16HV785 Microchip Technology Inc., PIC16HV785 Datasheet - Page 30

• Manufacturer Part Number: PIC16HV785
• Description: 20-pin Flash-based 8-bit Cmos Microcontroller
• Manufacturer: Microchip Technology Inc.

PIC16F785/HV785
3.4.2.2
The HFINTOSC is factory calibrated but can be
adjusted in software by writing to the OSCTUNE
register (Register 3-1).
The OSCTUNE register has a nominal tuning range of
±12%. The default value of the OSCTUNE register is
‘0’. The value is a 5-bit two’s complement number. Due
to process variation, the monotonicity and frequency
step cannot be specified.
REGISTER 3-1:
DS41249D-page 28
bit 7-5
bit 4-0
OSCTUNE Register
OSCTUNE: OSCILLATOR TUNING REGISTER (ADDRESS 90h)
Unimplemented: Read as ‘0’
TUN<4:0>: Frequency Tuning bits
01111 = Maximum frequency
01110 =
•
•
•
00001 =
00000 = Center frequency. Oscillator module is running at the calibrated frequency.
11111 =
•
•
•
10000 = Minimum frequency
bit 7
Legend:
R = Readable bit
-n = Value at POR
U-0
—
U-0
—
U-0
Preliminary
—
W = Writable bit
‘1’ = Bit is set
R/W-0
TUN4
When the OSCTUNE register is modified, the
HFINTOSC frequency will begin shifting to the new
frequency. The HFINTOSC clock will stabilize within
1 ms. Code execution continues during this shift. There
is no indication that the shift has occurred.
OSCTUNE does not affect the LFINTOSC frequency.
Operation of features that depend on the LFINTOSC
clock source frequency, such as the Power-up Timer
(PWRT), Watchdog Timer (WDT), Fail-Safe Clock
Monitor (FSCM) and peripherals, are not affected by
the change in frequency.
R/W-0
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
TUN3
R/W-0
TUN2
© 2006 Microchip Technology Inc.
x = Bit is unknown
R/W-0
TUN1
R/W-0
TUN0
bit 0