XC164-16 Datasheet, PDF (159/417 Pages) Infineon Technologies AG – 16-Bit Single-Chip Microcontroller with C166SV2 Core Volume 2 (of 2): Peripheral Units

XC164-16 Derivatives
Peripheral Units (Vol. 2 of 2)
Capture/Compare Unit 6 (CAPCOM6)
Figure 18-13 illustrates some more examples for compare waveforms. It is important to
note that in these examples, it is assumed that some of the compare values are changed
while the timer is running. This change is performed via a software preload of the
Shadow Register, CC6xSR. The value is transferred to the actual Compare Register
CC6xR with the T12 Shadow Transfer signal, T12_ST, which is assumed to be enabled.
f_T12
T12 Count
CDIR
CC6x
a)
b)
c)
d)
e)
f)
Down
Value n
CC6x = 2
CC6x = 1
CC6x = 3
CC6x = 4
CC6x = 5
CC6x = 3
Up
Value n+1
CC6x = 2
CC6x = 0
CC6x = 3
CC6x = 4
CC6x = 5
CC6x = 6
Down
Value n+2
CC6x = 1
CC6x = 0
CC6x = 3
CC6x = 4
CC6x = 5
CC6x = 6
Period
Value = 5
Zero
Up
Value n+3
CC6x = 1
CC6x = 0
CC6x = 3
CC6x = 4
CC6x = 5
CC6x = 6
MCT05517
Figure 18-13 Compare Waveform Examples
Example b) illustrates the transition to a duty cycle of 100%. First, a compare value of
0001_H is used, then changed to 0000_H. Please note that a low pulse with the length of
one T12 clock is still produced in the cycle where the new value 0000_H is in effect; this
pulse originates from the previous value 0001_H. In the following timer cycles, the State
Bit CCxST remains at 1, producing a 100% duty cycle signal. In this case, the compare
rule ‘zero-match AND compare-match’ is in effect.
User’s Manual
CAPCOM6_X, V2.0
18-15
V2.1, 2004-03