Timer B
M30240 Group
Rev.1.00 Sep 24, 2003 Page 176 of 360
2.3.3 Precautions
2.3.3.1 Timer mode
(1) At reset, the count start flag is set to “0”. Set a value in the Timer Bi register, then set the flag to “1”.
(2) Reading the Timer Bi register while a count is in progress allows reading, with arbitrary timing, the
value of the counter. Reading the Timer Bi register with the reload timing shown in Figure 2.38 gets
“FFFF
16
”. Reading the Timer Bi register after setting a value in the Timer Bi register with a count stopped
but before the counter starts counting gets a proper value.
Figure 2.38: Reading Timer Bi register
21
0
n n – 1
Counter value (Hex.)
21
0
FFFF n – 1
Read value (Hex.)
Reload
Time
n = reload register content