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EPSON
E0C6006 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)
4.8.3 I/O memory of clock timer
Table 4.8.3.1 shows the I/O addresses and the control bits for the clock timer.
Table 4.8.3.1 Control bits of clock timer
Address
Comment
D3
D2
Register
D1
D0
Name
Init
∗
1
1
0
0F4H
TM03
TM02
TM01
TM00
R
TM03
TM02
TM01
TM00
0
0
0
0
Timer data (16 Hz)
Timer data (32 Hz)
Timer data (64 Hz)
Timer data (128 Hz)
0F5H
TM13
TM12
TM11
TM10
R
TM13
TM12
TM11
TM10
0
0
0
0
Timer data (1 Hz)
Timer data (2 Hz)
Timer data (4 Hz)
Timer data (8 Hz)
0F3H
TMRUN
EIT2
EIT8
EIT32
R/W
TMRUN
EIT2
EIT8
EIT32
0
0
0
0
Run
Enable
Enable
Enable
Reset,Stop
Mask
Mask
Mask
Timer run/reset & stop
Interrupt mask register (clock timer 2 Hz)
Interrupt mask register (clock timer 8 Hz)
Interrupt mask register (clock timer 32 Hz)
0F1H
WDRST
IT2
IT8
IT32
W
R
WDRST
IT2
∗
4
IT8
∗
4
IT32
∗
4
Reset
0
0
0
Reset
Yes
Yes
Yes
–
No
No
No
Watchdog timer reset
Interrupt factor flag (clock timer 2 Hz)
Interrupt factor flag (clock timer 8 Hz)
Interrupt factor flag (clock timer 32 Hz)
∗
1
∗
2
Initial value at initial reset
Not set in the circuit
∗
5 Undefined
∗
3
∗
4
Always "0" being read
Reset (0) immediately after being read
TM00–TM03: Timer low-order data (0F4H)
TM10–TM13: Timer high-order data (0F5H)
The l28 Hz to 16 Hz timer data of the clock timer can be read from the TM00–TM03 register and 8 Hz to 1
Hz data can be read from the TM10–TM13 register. These eight bits are read-only, and write operations
are invalid.
At initial reset, the timer data is initialized to "00H".
TMRUN: Clock timer control (0F3H•D3)
Starts, stops and resets the clock timer.
When "1" is written: Run
When "0" is written: Reset and stop
Reading: Valid
The clock timer starts counting by writing "1" to the TMRUN register. When "0" is written, the clock timer
clears the count data and stops counting.
At initial reset, this register is set to "0".
EIT32, EIT8, EIT2: Interrupt mask registers (0F3H•D0–D2)
These registers are used to mask the clock timer interrupt.
When "1" is written: Enabled
When "0" is written: Masked
Reading: Valid
The interrupt mask registers (EIT32, EIT8, EIT2) mask the corresponding interrupt frequencies (32 Hz, 8
Hz, 2 Hz).
At initial reset, these registers are all set to "0".