NJU6543 Preliminary
(3) Command Register1
Command Register1 is used to set the duty ratio, the bias ratio, and the SEG driver/general purpose ports.
When the D7 to D6 bits of the 1st word are (1,0), the D5 ~ D0 bits are recognized as command data.
The contents of Command Register will be initialized as following when applying Power On Reset or Reset.
The Default Value of Command Register
• Duty ratio
• Bias ratio
• SEG driver/General purpose ports
: 1/4
: 1/3
: SEG drivers(SEG125,SEG126, SEG127, SEG128)
D7
D6
D5
D4
D3
D2
D1
D0
1
0
DS1
DS0
BS TSEL2 TSEL1 TSEL0
Flag bits
Duty ratio
Bias ratio SEG driver or general purpose ports
• Duty ratio
DS1 DS0
Duty ratio
0
0
1/4
0
1
1/3
1
0
1/2
*) Do not change the duty ratio during display ON.
**) If DS1 and DS0 are set as (1, 1), it set as the same 1/4Duty as (0, 0).
• Bias ratio
BS
0
1
Bias ratio
1/3
1/2
• SEG driver or general purpose ports
TSEL2 TSEL1 TSEL0 SEG125/P1 SEG126/P2 SEG127/P3 SEG128/P4
0
0
0
SEG125 SEG126 SEG127 SEG128
0
0
1
SEG125 SEG126 SEG127
P4
0
1
0
SEG125 SEG126
P3
P4
0
1
1
SEG125
P2
P3
P4
1
0
0
P1
P2
P3
P4
***) If TSEL2 ~ TSEL0 is set to (1, 0, 1), (1, 1, 0), (1, 1, 1) all outputs are used as segment drivers.
-6-
Ver.2008-11-28