HD6417750RF240V Datasheet, PDF (270/606 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2600 Series

Section 10 16-Bit Timer Pulse Unit (TPU)
10.9 Usage Notes
10.9.1 Module Stop Mode Setting
TPU operation can be disabled or enabled using the module stop control register. The initial
setting is for TPU operation to be halted. Register access is enabled by clearing module stop
mode. For details, refer to section 20, Power-Down Modes.
10.9.2 Input Clock Restrictions
The input clock pulse width must be at least 1.5 states in the case of single-edge detection, and at
least 2.5 states in the case of both-edge detection. The TPU will not operate properly at narrower
pulse widths.
In phase counting mode, the phase difference and overlap between the two input clocks must be at
least 1.5 states, and the pulse width must be at least 2.5 states. Figure 10.44 shows the input clock
conditions in phase counting mode.
TCLKA
(TCLKC)
TCLKB
(TCLKD)
Phase
Phase
differ-
differ-
Overlap _ence Overlap _ence
Pulse width
Pulse width
Pulse width
Pulse width
Notes: Phase difference and overlap : 1.5 states or more
Pulse width
: 2.5 states or more
Figure 10.44 Phase Difference, Overlap, and Pulse Width in Phase Counting Mode
10.9.3 Caution on Period Setting
When counter clearing on compare match is set, TCNT is cleared in the final state in which it
matches the TGR value (the point at which the count value matched by TCNT is updated).
Consequently, the actual counter frequency is given by the following formula:
φ
f=
(N + 1)
Rev. 7.00 Sep. 11, 2009 Page 234 of 566
REJ09B0211-0700