12 8-bit Timer (T8F)
12-16
EPSON
S1C17602 TECHNICAL MANUAL
0x4208/0x4288: 8-bit Timer Ch.x Interrupt Control Register (T8F_INTx)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
8-bit Timer Chx
Interrupt
Control Register
(T8F_INTx)
0x4208
0x4288
(16 bits)
D15–9 –
reserved
–
0 when being read.
D8
T8IE
8-bit timer interrupt enable
1 Enable
0 Disable
0
R/W
D7–1 –
reserved
–
0 when being read.
D0
T8IF
8-bit timer interrupt flag
1 Cause of
interrupt
occurred
0 Cause of
interrupt not
occurred
0
R/W Reset by writing 1.
Note: The indication "x" in the register name indicates the channel number (0 or 1).
0x4208: 8-bit Timer Ch.0 Interrupt Control Register (T8F_INT0)
0x4288: 8-bit Timer Ch.1 Interrupt Control Register (T8F_INT1)
D[15:9]
Reserved
D8
T8IE: 8-bit Timer Interrupt Enable Bit
Permits or prevents interrupts caused by counter underflows for each channel.
1 (R/W): Permit interrupt
0 (R/W): Prevent interrupt (default)
Setting T8IE to 1 permits 8-bit timer interrupt requests to the ITC; setting to 0 prevents interrupts.
D[7:1]
Reserved
D0
T8IF: 8-bit Timer Interrupt Flag
Interrupt flag indicating the counter underflow interrupt cause occurrence status for each channel.
1 (R): Interrupt cause present
0 (R): No interrupt cause (default)
1 (W): Reset flag
0 (W): Disable
T8IF is the T8F module interrupt flag. Setting T8IE (D8) to 1 sets the counter to 1 if an underflow
occurs during counting. An 8-bit timer interrupt request signal is output to the ITC at the same time. An
interrupt is generated if interrupt conditions are satisfied for the ITC and S1C17 core.
Writing 1 to this bit resets T8IF.
Note: To prevent interrupt recurrences, the T8 module interrupt flag T8IF must be reset within the
interrupt processing routine following an 8-bit timer interrupt.
To prevent unwanted interrupts, reset T8IF before permitting 8-bit timer interrupts with
T8IE.
The 8-bit timer uses one interrupt signal for Ch.0 and Ch.1 interrupt requests to the ITC. The
same interrupt processing routine is performed regardless of which interrupt is generated.
When using both channel interrupts, read out the interrupt flag in the T8F module as part of
the interrupt processing routine and check which channel generates the interrupt.