Chapter 4 Timer Functions
74 16-bit Timer Operation (timer 4)
[5-2-3 "Serial Interface
Transfer Timing"]
Setting the Added Pulse Position
The upper 8 bits of compare register 4 (TM4OCH) set the position of the added pulse. If the
TM4OCH register is set to X'00', an additional bit is not appended to the basic PWM
component. If the TM4OCH register is set to X'FF', an additional bit is repeatedly appended
to the 255 basic PWM components during the period. The relation between the value set in
the TM4OCH register and the added pulse is shown in the table below. If X'03' is set in the
TM4OCH register, bits are appended to pulse positions for X'01' and X'02', shown in table
4-3-1. The relation between the value set in the TM4OCH register and the position of the
added bit is shown in figure 4-3-5.
Table 4-3-1 Pulse-Added PWM OutputFigure
Figure 4-3-5 Pulse Added Type PWM Output
TM4OCH
Register setting
value
X '00'
X '01'
X '02'
X '10'
X '08'
X '04'
0 X '40' X '80' X 'C0' X 'FF'
PWM basic component
Repeated 256 times
Position of
added pulse
Position of added pulse X'87' Position of added pulse X'88'
Value Set in TM4OCH Register
Added Pulse Position (value of Tn)
00000000
00000001
10000000
01000000
00100000
00010000
00001000
00000100
00000010
(MSB) (LSB)
X'80'
X'40',X'C0'
X'20',X'60',X'A0',X'E0'
X'10',X'30',X'50',X'70',X'90',X'B0',X'D0',X'F0'
X'08',X'18',X'28',X'38',X'48',X'58' . . . . .,X'E8',X'F8'
X'04',X'0C',X'14',X'1C',X'24',X'2C' . . . . .,X'F4',X'FC'
X'02',X'06',X'0A',X'0E',X'12',X'16' . . . . .,X'FA',X'FE'
X'01',X'03',X'05',X'07',X'09',X'0B' . . . . .,X'FD',X'FF'