mc68hc908qf4 Freescale Semiconductor, Inc, mc68hc908qf4 Datasheet - Page 99

• Manufacturer Part Number: mc68hc908qf4
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

11.8.2 Oscillator Trim Register (OSCTRIM)
MC68HC908QF4 — Rev. 1.0
MOTOROLA
TRIM7–TRIM0 — Internal Oscillator Trim Factor Bits
These read/write bits change the size of the internal capacitor used by the
internal oscillator. By measuring the period of the internal clock and adjusting
this factor accordingly, the frequency of the internal clock can be fine tuned.
Increasing (decreasing) this factor by one increases (decreases) the period by
approximately 0.2% of the untrimmed period (the period for TRIM = $80). The
trimmed frequency is guaranteed not to vary by more than ±5% over the full
specified range of temperature and voltage. The reset value is $80, which sets
the frequency to 4.0 MHz (1.0 MHz bus speed) ±25%.
Address: $0038
Reset:
Read:
Write:
Freescale Semiconductor, Inc.
For More Information On This Product,
TRIM7
Bit 7
1
Figure 11-5. Oscillator Trim Register (OSCTRIM)
Go to: www.freescale.com
Oscillator Module (OSC)
TRIM6
6
0
TRIM5
5
0
TRIM4
4
0
TRIM3
3
0
Input/Output (I/O) Registers
TRIM2
2
0
Oscillator Module (OSC)
TRIM1
1
0
Data Sheet
TRIM0
Bit 0
0
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