Epson S1C63358, Technical Manual

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66
EPSON
S1C63358 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)
4.9.4 I/O memory of clock timer
Table 4.9.4.1 shows the I/O addresses and the control bits for the clock timer.
Table 4.9.4.1 Control bits of clock timer
Address Comment
D3 D2
Register
D1 D0 Name Init
∗
1 1 0
W R/W R
FF78H
0 0 TMRST TMRUN
0
∗
3
0
∗
3
TMRST
∗
3
TMRUN
–
∗
2
–
∗
2
Reset
0
Reset
Run
Invalid
Stop
Unused
Unused
Clock timer reset (writing)
Clock timer Run/Stop
R
FF79H
TM3 TM2 TM1 TM0
TM3
TM2
TM1
TM0
0
0
0
0
Clock timer data (16 Hz)
Clock timer data (32 Hz)
Clock timer data (64 Hz)
Clock timer data (128 Hz)
R
FF7AH
TM7 TM6 TM5 TM4
TM7
TM6
TM5
TM4
0
0
0
0
Clock timer data (1 Hz)
Clock timer data (2 Hz)
Clock timer data (4 Hz)
Clock timer data (8 Hz)
FFE6H
EIT3 EIT2 EIT1 EIT0
R/W
EIT3
EIT2
EIT1
EIT0
0
0
0
0
Enable
Enable
Enable
Enable
Mask
Mask
Mask
Mask
Interrupt mask register (Clock timer 1 Hz)
Interrupt mask register (Clock timer 2 Hz)
Interrupt mask register (Clock timer 8 Hz)
Interrupt mask register (Clock timer 16 Hz)
FFF6H
IT3 IT2 IT1 IT0
R/W
IT3
IT2
IT1
IT0
0
0
0
0
(R)
Yes
(W)
Reset
(R)
No
(W)
Invalid
Interrupt factor flag (Clock timer 1 Hz)
Interrupt factor flag (Clock timer 2 Hz)
Interrupt factor flag (Clock timer 8 Hz)
Interrupt factor flag (Clock timer 16 Hz)
*1 Initial value at initial reset
*2 Not set in the circuit
*3 Constantly "0" when being read
TM0–TM7: Timer data (FF79H, FF7AH)
The 128–1 Hz timer data of the clock timer can be read out with these registers. These eight bits are read
only, and writing operations are invalid.
By reading the low-order data (FF79H), the high-order data (FF7AH) is held until reading or for 0.48–1.5
msec (one of shorter of them).
At initial reset, the timer data is initialized to "00H".
TMRST: Clock timer reset (FF78H•D1)
This bit resets the clock timer.
When "1" is written: Clock timer reset
When "0" is written: No operation
Reading: Always "0"
The clock timer is reset by writing "1" to TMRST. When the clock timer is reset in the RUN status, opera-
tion restarts immediately. Also, in the STOP status the reset data is maintained. No operation results
when "0" is written to TMRST.
This bit is write-only, and so is always "0" at reading.