Datasheet

Section 11 14-Bit PWM
Rev. 6.00 Aug 04, 2006 page 413 of 680
REJ09B0145-0600
11.2.2 PWM Data Registers U and L (PWDRU, PWDRL)
Bit
Initial value
Read/Write
7

1

6

1

5
PWDRU5
0
W
4
PWDRU4
0
W
3
PWDRU3
0
W
0
PWDRU0
0
W
2
PWDRU2
0
W
1
PWDRU1
0
W
PWDRU
Bit
Initial value
Read/Write
7
PWDRL7
0
W
6
PWDRL6
0
W
5
PWDRL5
0
W
4
PWDRL4
0
W
3
PWDRL3
0
W
0
PWDRL0
0
W
2
PWDRL2
0
W
1
PWDRL1
0
W
PWDRL
PWDRU and PWDRL form a 14-bit write-only register, with the upper 6 bits assigned to PWDRU
and the lower 8 bits to PWDRL. The value written to PWDRU and PWDRL gives the total high-
level width of one PWM waveform cycle.
When 14-bit data is written to PWDRU and PWDRL, the register contents are latched in the PWM
waveform generator, updating the PWM waveform generation data. The 14-bit data should
always be written in the following sequence:
1. Write the lower 8 bits to PWDRL.
2. Write the upper 6 bits to PWDRU.
PWDRU and PWDRL are write-only registers. If they are read, all bits are read as 1.
Upon reset, PWDRU and PWDRL are initialized to H'C000.