Datasheet

PIC24FJ128GC010 FAMILY
DS30009312B-page 164  2012-2013 Microchip Technology Inc.
REGISTER 9-3: OSCTUN: FRC OSCILLATOR TUNE REGISTER
R/W-0 U-0 R/W-0 R/W-0 R-0 R/W-0 R-0 R/W-0
STEN —STSIDLSTSRC
(1)
STLOCK STLPOL STOR STORPOL
bit 15 bit 8
U-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
— — TUN5
(2)
TUN4
(2)
TUN3
(2)
TUN2
(2)
TUN1
(2)
TUN0
(2)
bit 7 bit 0
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 15 STEN: FRC Self-Tune Enable bit
1 = FRC self-tuning is enabled; TUNx bits are controlled by hardware
0 = FRC self-tuning is disabled; application may optionally control TUNx bits
bit 14 Unimplemented: Read as ‘0’
bit 13 STSIDL: FRC Self-Tune Stop in Idle bit
1 = Self-tuning stops during Idle mode
0 = Self-tuning continues during Idle mode
bit 12 STSRC: FRC Self-Tune Reference Clock Source bit
(1)
1 = FRC is tuned to approximately match the USB host clock tolerance
0 = FRC is tuned to approximately match the 32.768 kHz SOSC tolerance
bit 11 STLOCK: FRC Self-Tune Lock Status bit
1 = FRC accuracy is currently within ±0.2% of the STSRC reference accuracy
0 = FRC accuracy may not be within ±0.2% of the STSRC reference accuracy
bit 10 STLPOL: FRC Self-Tune Lock Interrupt Polarity bit
1 = A self-tune lock interrupt is generated when STLOCK is ‘0’
0 = A self-tune lock interrupt is generated when STLOCK is ‘1’
bit 9 STOR: FRC Self-Tune Out of Range Status bit
1 = STSRC reference clock error is beyond the range of TUN<5:0>; no tuning is performed
0 = STSRC reference clock is within the tunable range; tuning is performed
bit 8 STORPOL: FRC Self-Tune Out of Range Interrupt Polarity bit
1 = A self-tune out of range interrupt is generated when STOR is ‘0’
0 = A self-tune out of range interrupt is generated when STOR is ‘1’
bit 7-6 Unimplemented: Read as ‘0’
bit 5-0 TUN<5:0>: FRC Oscillator Tuning bits
(2)
011111 = Maximum frequency deviation
011110 =
  
000001 =
000000 = Center frequency, oscillator is running at factory calibrated frequency
111111 =
  
100001 =
100000 = Minimum frequency deviation
Note 1: Use of either clock tuning reference source has specific application requirements. See Section 9.5 “FRC
Active Clock Tuning” for details.
2: These bits are read-only when STEN = 1.