CHAPTER 6 PERIPHERAL HARDWARE FUNCTION
174 Users Manual U10676EJ3V0UM
(2) Note on starting timer
Usually, count register Tn and interrupt request flag IRQTn are cleared when the timer is started (bit 3 of TMn
is set to 1). However, if the timer is in an operation mode, and if IRQTn is set as soon as the timer is started,
IRQTn may not be cleared. This does not pose any problem when IRQTn is used as a vector interrupt. In
an application where IRQTn is being tested, however, IRQTn is not set after the timer has been started and
this poses a problem. Therefore, there is a possibility that the timer could be started as soon as IRQTn is
set to 1, either stop the timer once (by clearing the bit 2 of TMn to 0), or start the timer two times.
Example If there is a possibility that timer could be started as soon as IRQTn is set
SEL MB15
MOV XA, #0
MOV TMn, XA ; Stops timer
MOV XA, #4CH
MOV TMn, XA ; Restarts
Or,
SEL MB15
SET1 TMn.3
SET1 TMn.3 ; Restarts
Remark n = 0 to 2