C505_9708 SIEMENS [Siemens Semiconductor Group], C505_9708 Datasheet - Page 97

• Manufacturer Part Number: C505_9708
• Description: 8-Bit CMOS Microcontroller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

Figure 6-18
Modulation Range of a PWM Signal, generated with a Timer 2/CCx Register Combination in
Compare Mode 0*
The following example shows how to calculate the modulation range for a PWM signal. To calculate
with reasonable numbers, a reduction of the resolution to 8-bit is used. Otherwise (for the maximum
resolution of 16-bit) the modulation range would be so severely limited that it would be negligible.
Example:
Timer 2 in auto-reload mode; contents of reload register CRC = FF00 H
Restriction of modulation range = 1 / (256 x 2) x 100% = 0.195%
This leads to a variation of the duty cycle from 0.195% to 99.805% for a timer 2/CCx register
configuration when 8 of 16 bits are used.
Semiconductor Group
a)
b)
CCHx/CCLx = 0000 or = CRCH/CRCL (maximum duty cycle)
CCHx/CCLx = FFFF (minimum duty cycle)
P1.x
P1.x
H
H
6-35
Appr. 1/2 Machine Cycle
Appr. 1/2 Machine Cycle
On-Chip Peripheral Components
MCT01907
H
L
H
L
C505 / C505C
1997-08-01