DF2211NP24V Renesas Technology / Hitachi Semiconductor, DF2211NP24V Datasheet - Page 371

• Manufacturer Part Number: DF2211NP24V
• Description: H8S/2200 Series, 2212 Group, USB, RTC, HSS TNP-64B; Vcc= 2.7 to 3.6 volts, Temp= -20 to 75 C; Package: PVQN0064LB-A
• Manufacturer: Renesas Technology / Hitachi Semiconductor

9.5.5
In phase counting mode, the phase difference between two external clock inputs is detected and
TCNT is incremented/decremented accordingly. This mode can be set for channels 1 and 2. When
phase counting mode is set, an external clock is selected as the counter input clock and TCNT
operates as an up/down-counter regardless of the setting of bits TPSC2 to TPSC0 and bits CKEG1
and CKEG0 in TCR. However, the functions of bits CCLR1 and CCLR0 in TCR, and of TIOR,
TIER, and TGR are valid, and input capture/compare match and interrupt functions can be used.
This can be used for two-phase encoder pulse input. When overflow occurs while TCNT is
counting up, the TCFV flag in TSR is set; when underflow occurs while TCNT is counting down,
the TCFU flag is set. The TCFD bit in TSR is the count direction flag. Reading the TCFD flag
provides an indication of whether TCNT is counting up or down. Table 9.19 shows the
correspondence between external clock pins and channels.
Table 9.19 Phase Counting Mode Clock Input Pins
Example of Phase Counting Mode Setting Procedure: Figure 9.25 shows an example of the
phase counting mode setting procedure.
Channels
When channel 1 is set to phase counting mode
When channel 2 is set to phase counting mode
Phase Counting Mode
Figure 9.25 Example of Phase Counting Mode Setting Procedure
Select phase counting mode
<Phase counting mode>
Phase counting mode
Start count
[1]
[2]
[1]
[2]
Select phase counting mode with bits MD3 to
MD0 in TMDR.
Set the CST bit in TSTR to 1 to start the count
operation.
A-Phase
TCLKC
TCLKA
Rev.7.00 Dec. 24, 2008 Page 317 of 698
External Clock Pins
B-Phase
TCLKB
TCLKD
REJ09B0074-0700