Figure 13.6-1 Changing Set Values During Operation Of Remote-Control Transmission Frequency Generator; Figure 13.6-2 Remote-Control Output Function - Fujitsu F2MC-8L Series Hardware Manual

CHAPTER 13 REMOTE-CONTROL TRANSMISSION FREQUENCY GENERATOR
Figure 13.6-1 Changing Set Values during Operation of Remote-control Transmission Frequency
Cycle set value
(RCR2: SCL)
"H" width set value
(RCR1: HSC)
RCO output waveform
*1: Since the current counter value is smaller than the new set value, the set value remains valid in the current cycle.
*2: Since the cycle is set to a value smaller than the current counter value, no match is detected, resulting in an
overflow.
*3: Since the "H" width is set to a value smaller than the current counter value, no match is detected until the next cycle.
Operation of output stopped
Right after sertting Output enable bit (RCEN) in remote-control transmission frequency control
register 2 (RCR2) to be "0", it changes to port output. So,be careful that there is a case where
output pulth become narrow as shown 13.6-2.
Remote-control Output
PCEN
remote-control output
Error
Activating the counter by the program does not synchronize with the start of the selected count
clock. Therefore, the time difference between the time until a match of the counter value and
the compare value for the "H" width and cycle is detected, and the time of the count clock cycle,
may be shorter by a maximum of one cycle. Figure 13.6-3 shows the time difference that
occurs on starting counter operation.
292
Counter value
3F
H
1
*
1
*
00
H

Figure 13.6-2 Remote-control Output Function

Generator
Overflow
2
*
Extended for overflow
port output(PDR:L)
3
*
1 cycle
remote-control output