M16C28 Datasheet, PDF (153/423 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/Tiny SERIES

M16C/28 Group (M16C/28, M16C/28B)
12. Timer
12.3.1 Position-Data-Retain Function
This function is used to retain the position data synchronously with the three-phase waveform
output.There are three position-data input pins for U, V, and W phases.
A trigger to retain the position data (hereafter, this trigger is referred to as "retain trigger") can be selected
by the PDRT bit in the PDRF register. This bit selects the retain trigger to be the falling edge of each
positive phase, or the rising edge of each positive phase.
12.3.1.1 Operation of the Position-data-retain Function
Figure 12.35 shows a usage example of the position-data-retain function (U phase) when the retain
trigger is selected as the falling edge of the positive signal.
(1) At the falling edge of the U-phase waveform ouput, the state at pin IDU is transferred to the PDRU
bit in the PDRF register.
(2) Until the next falling edge of the Uphase waveform output,the above value is retained.
1
2
Carrier wave
U-phase waveform output
U-phase waveform output
Pin IDU
PDRU bit
Transferred
Transferred
Transferred
Transferred
Note: The retain trigger is the falling edge of the positive signal.
Figure 12.35 Usage Example of Position-data-retain Function (U phase )
Rev. 2.00 Jan. 31, 2007 ^{page 133} of 385
REJ09B0047-0200