C8051T610DB28 Silicon Laboratories Inc, C8051T610DB28 Datasheet - Page 199

• Manufacturer Part Number: C8051T610DB28
• Description: DAUGHTER BOARD T610 28QFN SOCKET
• Manufacturer: Silicon Laboratories Inc

Specifications of C8051T610DB28

• Module/board Type: Socket Module - QFN
• Processor To Be Evaluated: C8051T61x
• Interface Type: USB
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: C8051T610DK
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 336-1506

26.3.6. 16-Bit Pulse Width Modulator Mode
A PCA module may also be operated in 16-Bit PWM mode. In this mode, the 16-bit capture/compare mod-
ule defines the number of PCA clocks for the low time of the PWM signal. When the PCA counter matches
the module contents, the output on CEXn is asserted high; when the 16-bit counter overflows, CEXn is
asserted low. To output a varying duty cycle, new value writes should be synchronized with PCA CCFn
match interrupts. 16-Bit PWM Mode is enabled by setting the ECOMn, PWMn, and PWM16n bits in the
PCA0CPMn register. For a varying duty cycle, match interrupts should be enabled (ECCFn = 1 AND MATn
= 1) to help synchronize the capture/compare register writes. If the MATn bit is set to 1, the CCFn flag for
the module will be set each time a 16-bit comparator match (rising edge) occurs. The CF flag in PCA0CN
can be used to detect the overflow (falling edge). The duty cycle for 16-Bit PWM Mode is given by
Equation 26.3.
Important Note About Capture/Compare Registers: When writing a 16-bit value to the PCA0 Cap-
ture/Compare registers, the low byte should always be written first. Writing to PCA0CPLn clears the
ECOMn bit to 0; writing to PCA0CPHn sets ECOMn to 1.
Using Equation 26.3, the largest duty cycle is 100% (PCA0CPn = 0), and the smallest duty cycle is
0.0015% (PCA0CPn = 0xFFFF). A 0% duty cycle may be generated by clearing the ECOMn bit to 0.
PCA0CPLn
Write to
Reset
PCA0CPHn
Write to
0
ENB
ENB
1
P
W
M
1
6
n
1
E
C
O
M
n
PCA0CPMn
C
A
P
P
n
0 0 x 0
C
A
P
N
n
M
A
T
n
PCA Timebase
O
G
T
n
Equation 26.3. 16-Bit PWM Duty Cycle
P
W
M
n
E
C
C
F
n
x
Figure 26.9. PCA 16-Bit PWM Mode
Duty Cycle
Enable
PCA0CPHn
PCA0H
=
16-bit Comparator

---------------------------------------------------- -
Rev 1.0
65536 PCA0CPn
PCA0CPLn
C8051T610/1/2/3/4/5/6/7
PCA0L
–
65536
Overflow
match

S
R
SET
CLR
Q
Q
CEXn
Crossbar
Port I/O
199