h8s-2169 Renesas Electronics Corporation., h8s-2169 Datasheet - Page 430

• Manufacturer Part Number: h8s-2169
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 13 Timer Connection
13.3.5
By using the timer connection TMR1, the fall of the IVI signal can be shifted backward by the
specified number of IHI signal waveforms. Also, the fall of the IVI signal can be synchronized
with the rise of the IHI signal.
To perform 8-bit timer divided waveform period measurement, TCNT in TMR1 is set to count
external clock (IHI signal) pulses, and to be cleared on the rising edge of the external reset signal
(inverse of the IVI signal). The number of IHI signal pulses until the fall of the IVI signal is
written in TCORB.
Since the IVI signal supplied to the IVO signal selection circuit is normally set on the rise of the
IVI signal and reset on the fall, its waveform is the same as that of the original IVI signal. When
fall modification is selected, a reset is performed on a TMR1 TCORB compare-match.
The fall of the waveform generated in this way can be synchronized with the rise of the IHI signal,
regardless of whether or not fall modification is selected.
Examples of TMR1 TCORB, TCR, and TCSR settings are shown in table 13.7, and the fall
modification/IHI synchronization timing chart is shown in figure 13.7.
Table 13.7 Examples of TCR, TCSR, and TCORB Settings
Rev. 3.00 Jan 18, 2006 page 402 of 1044
REJ09B0280-0300
Register
TCR in
TMR1
TCSR in
TMR1
TCORB in TMR1
IVI Signal Fall Modification and IHI Synchronization
Bit(s)
7
6
5
4 and 3
2 to 0
3 to 0
Abbreviation
CMIEB
CMIEA
OVIE
CCLR1,
CCLR0
CKS2 to CKS0
OS3 to OS0
Contents
0
0
0
11
101
0011
1001
H'03
(example)
Description
Interrupts due to compare-match and
overflow are disabled
TCNT is cleared by the rising edge of the
external reset signal (inverse of the IVI
signal)
TCNT is incremented on the rising edge of
the external clock (IHI signal)
Not changed by compare-match B; output
inverted by compare-match A (toggle output)
or
when TCORB
compare-match B, 0 output on compare-
match A
Compare-match on the 4th (example) rise of
the IHI signal after the rise of the inverse of
the IVI signal
TCORA, 1 output on