Datasheet

PIC32MX1XX/2XX
DS61168E-page 98 Preliminary  2011-2012 Microchip Technology Inc.
REGISTER 8-2: OSCTUN: FRC TUNING REGISTER
Bit
Range
Bit
31/23/15/7
Bit
30/22/14/6
Bit
29/21/13/5
Bit
28/20/12/4
Bit
27/19/11/3
Bit
26/18/10/2
Bit
25/17/9/1
Bit
24/16/8/0
31:24
U-0 U-0 U-0 U-0 U-0 U-0 U-0 U-0
— — — — — — — —
23:16
U-0 R-0 U-0 U-0 U-0 U-0 U-0 U-0
— — — — — — — —
15:8
U-0 R-0 U-0 U-0 U-0 U-0 U-0 U-0
— — — — — — — —
7:0
U-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
— — TUN<5:0>
(1)
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 31-6 Unimplemented: Read as ‘0’
bit 5-0 TUN<5:0>: FRC Oscillator Tuning bits
(1)
100000 = Center frequency -12.5%
100001 =
•
•
•
111111 =
000000 = Center frequency. Oscillator runs at minimal frequency (8 MHz)
000001 =
•
•
•
011110 =
011111 = Center frequency +12.5%
Note 1: OSCTUN functionality has been provided to help customers compensate for temperature effects on the
FRC frequency over a wide range of temperatures. The tuning step size is an approximation, and is neither
characterized, nor tested.
Note: Writes to this register require an unlock sequence. Refer to Section 6. “Oscillator” (DS61112) in the
“PIC32 Family Reference Manual” for details.