Epson RX-8581JE User Manual

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Page - 15 
MQ372-02
 
 
5) TIE (Timer Interrupt Enable) bit 
When a fixed-cycle timer interrupt event occurs (when the TF bit value changes from "0" to "1"), this bit's value 
specifies whether an interrupt signal is generated (/INT status changes from Hi-Z to low) or is not generated 
(/INT status remains Hi-Z).   
TIE 
Data Description 
 
1) When a fixed-cycle timer interrupt event occurs, an interrupt signal is not 
generated or is canceled (/INT status remains Hi-Z). 
2) When a fixed-cycle timer interrupt event occurs, the interrupt signal is 
canceled (/INT status changes from low to Hi-Z).   
 ∗
 
Even when the TIE bit value is "0" another interrupt event may change the /INT status to low (or 
may hold /INT =
 
"L").  
Write/Read
When a fixed-cycle timer interrupt event occurs, an interrupt signal is 
generated (/INT status changes from Hi-Z to low). 
 ∗
 
When a fixed-cycle timer interrupt event has been generated low-level output from the /INT pin 
occurs only when the value of the control register's TIE bit is "1". Up to 7.8 ms after the interrupt 
occurs, the /INT status is automatically cleared (/INT status changes from low to Hi-Z). 
 
 
8.3.3. Fixed-cycle timer interrupt interval (example) 
 
Source clock 
Timer 
Counter 
setting 
4096 Hz 
 
TSEL1,0 = 0,0 
64 Hz 
 
TSEL1,0 = 0,1
 
"Second" 
update 
 
TSEL1,0 = 1,0
 
"Minute" 
update 
 
TSEL1,0 = 1,1
 
0  
 
 
 
 
1  
244.14 
µ
15.625 ms
1 s 
1 min 
2  
488.28 
µ
31.25 ms
2 s 
2 min 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
41 
 
10.010 ms 
640.63 ms
41 s 
41 min 
205 
 
50.049 ms 
3.203 s 
205 s 
205 min 
410 
 
100.10 ms 
6.406 s 
410 s 
410 min 
2048 
 
500.00 ms 
32.000 s 
2048 s 
2048 min 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4095 
 
0.9998 s 
63.984 s 
4095 s 
4095 min 
 
 Time error in fixed-cycle timer 
A time error in the fixed-cycle timer will produce a positive or negative time period error in the selected 
source clock. The fixed-cycle timer's time is within the following range relative to the time setting.   
 
 
(Fixed-cycle timer's time setting (
 source clock period) to (timer's time setting) 
   
) The timer's time setting = source clock period 
×
 timer counter's division value. 
 
 
 The time actually set to the timer is adjusted by adding the time described above to the 
communication time for the serial data transfer clock used for the setting.   
 
 
8.3.4. Fixed-cycle timer start timing 
 
Counting down of the fixed-cycle timer value starts at the rising edge of the SCL signal that occurs when the TE 
value is changed from "0" to "1"
 
(after bit 0 is transferred).   
 
 
TSEL0
TE
 
0
 
0
 
TSEL1
Operation of timer
/INT pin 
SDA pin 
SCL pin
 
Internal timer 
Address D
ACK