CHAPTER 10 TIMER/COUNTER FUNCTION (REAL-TIME PULSE UNIT)
User’s Manual U14359EJ4V0UM
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(2) Compare registers D0 to D3 (CMD0 to CMD3)
CMDn and the TMDn register count value are compared, and an interrupt request signal (INTCMDn) is
generated when a match occurs. TMDn is cleared, in synchronization with this match. If the TMDCAEn bit of
the TMCDn register is set to 0, a reset is performed asynchronously, and the registers are initialized (n = 0 to
3).
The CMDn registers are configured with a master/slave configuration. When a CMDn register is written, data
is first written to the master register and then the master register data is transferred to the slave register. In a
compare operation, the slave register value is compared with the count value of the TMDn register. When a
CMDn register is read, data in the master side is read out.
CMDn can be read or written in 16-bit units.
Cautions 1. A write operation to a CMDn register requires 4 clocks until the value that was set in the
CMDn register is transferred to internal units. When writing continuously to the CMDn
register, be sure to reserve a time interval of at least 4 clocks.
2. The CMDn register can be overwritten only once in a single TMDn register cycle (from
0000H until an INTCMDn interrupt is generated due to a match of the TMDn register and
CMDn register). If this cannot be secured by the application, make sure that the CMDn
register is not overwritten during timer operation.
3. Note that a match signal will be generated after an overflow if a value less than the
counter value is written in the CMDn register during TMDn register operation (Figure 10-
13).
CMD1
FFFFF552H
0000H
CMD2
FFFFF562H
0000H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
CMD0
FFFFF542H
0000H
Address
After reset
0
CMD3
FFFFF572H
0000H
Содержание V850E/MA1
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