MC9S08GB60 Datasheet, PDF (166/290 Pages) Motorola, Inc – Microcontrollers

Timer/PWM (TPM) Module
Bit 7
6
5
4
3
2
1
Bit 0
Read:
Bit 15
14
13
12
11
10
Write:
9
Bit 8
Reset: 0
0
0
0
0
0
0
0
Figure 10-11. Timer x Channel Value Register High (TPMxCnVH)
Bit 7
6
5
4
3
2
1
Bit 0
Read:
Bit 7
6
5
4
3
2
1
Bit 0
Write:
Reset: 0
0
0
0
0
0
0
0
Figure 10-12. Timer x Channel Value Register Low (TPMxCnVL)
In input capture mode, reading either byte (TPMxCnVH or TPMxCnVL) latches the contents of both bytes
into a buffer where they remain latched until the other byte is read. This latching mechanism also resets
(becomes unlatched) when the TPMxCnSC register is written.
In output compare or PWM modes, writing to either byte (TPMxCnVH or TPMxCnVL) latches the value
into a buffer. When both bytes have been written, they are transferred as a coherent 16-bit value into the
timer channel value registers. This latching mechanism may be manually reset by writing to the
TPMxCnSC register.
This latching mechanism allows coherent 16-bit writes in either order, which is friendly to various
compiler implementations.
MC9S08GB/GT Data Sheet, Rev. 2.3
166
Freescale Semiconductor