Table of Contents
Advertisement
CHAPTER 13 8/16-BIT UP/DOWN COUNTER/TIMER
13.5.1 Reload/compare function
The 8/16-bit up/down counter/timer has reload and compare functions. These two
functions may be mixed for processing.
■
Selection of reload and compare functions
Table 13.5-3 shows an example of selecting reload and compare functions.
Table 13.5-3 Selection example of reload/compare function
RLDE, UCRE
00
01
10
11
■
Reload function
At the start of the reload function, the RCR value is transferred to UDCR at the timing of the
down-count clock next to the clock in which an underflow occurs. In this example, UDFF is
specified, and an interrupt request occurs.
In a mode where there is no down counting (decrement), the start of this function is disabled.
(0FFFF
)
H
0FF
H
RCR
00
H
280
Reload/compare prohibit (initial value)
B
Compare permit
B
Reload permit
B
Reload/compare permit
B
Figure 13.5-3 Outline of reload function operation
Reload/interrupt generated
Underflow
Reload and compare functions
Reload/interrupt generated
Underflow
Advertisement
Table of Contents
