Specifications

24 EPSON S1C60N04 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)
4.6.3 I/O memory of LCD driver
Table 4.6.3.1 shows the control bits of the LCD driver and their addresses. Figure 4.6.3.1 shows the
display memory map.
Table 4.6.3.1 Control bits of LCD driver
Address Comment
D3 D2
Register
D1 D0 Name Init
∗1
10
∗1
∗2
Initial value at initial reset
Not set in the circuit
∗3
∗4
Always "0" being read
Reset (0) immediately after being read
0FBH
0 0 0 PDON
RR/W
0
∗ 3
0
∗ 3
0
∗ 3
PDON
–
∗ 2
–
∗ 2
–
∗ 2
0
–
–
–
On
–
–
–
Off
Unused
Unused
Unused
LCD power supply on/off control
Address 0123456789ABCDEF
090
0A0
Display memory (Write only)
32 words x 4 bits
Fig. 4.6.3.1 Display memory map
PDON: LCD power supply On/Off control (0FBH•D0)
Controls the power supply for LCD display.
When 1 is written: LCD power On
When 0 is written: LCD power Off
Reading: Valid
By writing 1 to PDON, the LCD display can work normally. When 0 is written, all the segment and
common signals will go to the same voltage level, and the LCD display goes off.
This control dose not affect the contents of display memory.
After an initial reset, this register is set to 0.
Display memory (090H–0AFH)
The LCD segments are turned on or off according to this data.
When 1 is written: On
When 0 is written: Off
Reading: Invalid
By writing data into the display memory allocated to the LCD segment (on the panel), the segment can be
turned on or off.
After an initial reset, the contents of the display memory are undefined.
4.6.4 Programming note
Because the display memory is for writing only, re-writing the contents with computing instructions (e.g.,
AND, OR, etc.) which come with read-out operations is not possible. To perform bit operations, a buffer
to hold the display data is required on the RAM.