MC68HC812A4 Datasheet, PDF (189/342 Pages) Motorola, Inc – 16-bit device composed of standard on-chip peripheral modules connected by an intermodule bus. Modules include

Standard Timer Module
Registers and Reset Initialization
12.6.5 Timer Counter Registers
Address: $0084
Bit 7
6
5
4
3
2
1
Bit 0
Read: Bit 15 Bit 14 Bit 13 Bit 12 Bit 11 Bit 10 Bit 9
Bit 8
Write:
Reset: 0
0
0
0
0
0
0
0
= Unimplemented
Figure 12-8. Timer Counter Register High (TCNTH)
Address: $0085
Bit 7
6
5
4
3
2
1
Bit 0
Read: Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Write:
Reset: 0
0
0
0
0
0
0
0
= Unimplemented
Figure 12-9. Timer Counter Register Low (TCNTL)
Read: Anytime
Write: Only in special modes; has no effect in normal modes
Use a double-byte read instruction to read the timer counter. Two
single-byte reads return a different value than a double-byte read.
NOTE:
The period of the first count after a write to the TCNT registers may be a
different size because the write is not synchronized with the prescaler
clock.
Advance Information
MOTOROLA
Standard Timer Module
MC68HC812A4 — Rev. 3.0
189