MC68HC908QY2 MOTOROLA [Motorola, Inc], MC68HC908QY2 Datasheet - Page 112

• Manufacturer Part Number: MC68HC908QY2
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

Oscillator Module (OSC)
8.9.2 Oscillator Trim Register (OSCTRIM)
112
MC68HC908QY4•MC68HC908QT4•MC68HC908QY2•MC68HC908QT2•MC68HC908QY1•MC68HC908QT1
Address: $0038
TRIM7–TRIM0 — Internal Oscillator Trim Factor Bits
Reset:
Read:
Write:
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 appoximately 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 12.8 MHz (3.2 MHz bus speed) ±25%.
TRIM7
Bit 7
Figure 8-4. Oscillator Trim Register (OSCTRIM)
1
Oscillator Module (OSC)
TRIM6
6
0
TRIM5
5
0
TRIM4
4
0
TRIM3
3
0
TRIM2
2
0
TRIM71
1
0
MOTOROLA
TRIM0
Bit 0
0