PIC16F946T-I/PT Microchip Technology, PIC16F946T-I/PT Datasheet - Page 80

• Manufacturer Part Number: PIC16F946T-I/PT
• Description: Microcontroller
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F946T-I/PT

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 14KB (8K x 14)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 336 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TFQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: MA160011 - DAUGHTER BOARD PICDEM LCD 16F91X
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

PIC16F946
4.4.2.1
The HFINTOSC is factory calibrated but can be
adjusted in software by writing to the OSCTUNE
register (Register 4-2).
The OSCTUNE register has a 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 4-2:
DS41265A-page 78
bit 7-5
bit 4-0
OSCTUNE Register
OSCTUNE – OSCILLATOR TUNING RESISTOR (ADDRESS: 90h)
bit 7
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
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
TUN3
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
R/W-0
TUN2
© 2005 Microchip Technology Inc.
x = Bit is unknown
R/W-0
TUN1
R/W-0
TUN0
bit 0