PIC16F946 Datasheet, PDF (74/274 Pages) Microchip Technology – 64-Pin Flash-Based, 8-Bit CMOS Microcontrollers with LCD Driver and nanoWatt Technology

PIC16F946
REGISTER 4-1:
bit 7
bit 6-4
bit 3
bit 2
bit 1
bit 0
OSCCON – OSCILLATOR CONTROL REGISTER (ADDRESS: 8Fh)
U-0
R/W-1 R/W-1 R/W-0
R-q
R-0
R-0
—
IRCF2
IRCF1
IRCF0 OSTS⁽¹⁾
HTS
LTS
bit 7
Unimplemented: Read as ‘0’
IRCF<2:0>: Internal Oscillator Frequency Select bits
000 =
001 =
010 =
011 =
100 =
101 =
110 =
111 =
31 kHz
125 kHz
250 kHz
500 kHz
1 MHz
2 MHz
4 MHz
8 MHz
OSTS: Oscillator Start-up Time-out Status bit
1 = Device is running from the external system clock defined by FOSC<2:0>
0 = Device is running from the internal system clock (HFINTOSC or LFINTOSC)
HTS: HFINTOSC (High Frequency – 8 MHz to 125 kHz) Status bit
1 = HFINTOSC is stable
0 = HFINTOSC is not stable
LTS: LFINTOSC (Low Frequency – 31 kHz) Stable bit
1 = LFINTOSC is stable
0 = LFINTOSC is not stable
SCS: System Clock Select bit
1 = Internal oscillator is used for system clock
0 = Clock source defined by FOSC<2:0>
R/W-0
SCS
bit 0
Note 1: The value of the OSTS bit on device power-up is dependent on the value of the
Configuration Word (CONFIG) of the device. The value of the OSTS bit will be ‘0’
on a device Power-on Reset (POR) or any automatic clock switch, which may occur
from Two-Speed Start-up or Fail-Safe Clock Monitor, if the following conditions are
true:
OSTS = 0 if:
FOSC<2:0> = 000 (LP) or 001 (XT) or 010 (HS)
and
IESO = 1 or FSCM = 1
(IESO will be enabled automatically if FSCM is enabled)
If any of the above conditions are not met, the value of the OSTS bit will be ‘1’ on
a device POR. See Section 4.6 “Two-Speed Clock Start-up Mode” and
Section 4.7 “Fail-Safe Clock Monitor” for more details.
Legend:
R = Readable bit
W = Writable bit
- n = Value at POR
‘1’ = Bit is set
q = value depends on condition
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared x = Bit is unknown
DS41265A-page 72
Preliminary
© 2005 Microchip Technology Inc.