NJU3426 NJR Corporation, NJU3426 Datasheet - Page 8

• Manufacturer Part Number: NJU3426
• Description: 16-SEGMENT × 14-Digit VFD Controller / Driver
• Manufacturer: NJR Corporation

NJU3426
(5) SERIAL DATA TRANSMISSION
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Communication between the NJU3426 and MPU uses the serial data transmission with synchronous clock, and 8 bits
serial data constitutes 1 word. Each bit on the SI pin is fetched at the rising edge of the serial clock (SCK), and the
entire 8 bits are loaded as 1 word at the rising edge of the chip select (CSb).
During one communication, multiple words can be transferred continuously. The 1
RAM address”, “Command register 1” or “Command register 2”. When the 1
ascending words must be display data. When it’s the “Command register 1 or 2”, the 2
ignored.
Serial input data
CSb
SCK
SCK
SI
DATA FORMAT FOR THE 1
DISPLAY DATA RAM ADRESS
COMMAND DATA 1
COMMAND DATA 2
SERIAL DATA FOR THE 2
SI
When the 1
When the 1
B7
B7
B7
0
1
0
DT2
B6
B6
B6
st
0
1
st
word is the “Command register 1 or 2”, the 2
word is the “Display data RAM address”, the 2
D0
DT1
B5
B5
B5
*
*
WORD 1
SERIAL DATA TRANSMISSION FORMAT
ND
ST
D1
AD4
DT0
AND ASCENDING WORDS
B4
B4
B4
WORD
*
SERIAL DATA TIMING
D2
AD3
DSP
DS3
B3
B3
B3
WORD 2
D3
AD2
DE2
DS2
B2
B2
B2
D4
AD1
DE1
DS1
nd
B1
B1
B1
and ascending words are ignored.
nd
D5
and ascending words must be display data.
AD0
DE0
DS0
B0
B0
B0
st
word is RAM address data, the 2
D6
st
*:don’t care
*:don’t care
*:don’t care
word must be either “Display data
WORD n
nd
D7
and ascending words are
Ver.2003-03-06
nd
and