NJU3426 NJR Corporation, NJU3426 Datasheet - Page 3

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

(1) ADDRESS COUNTER
Ver.2003-03-06
T
T
T
T
T
T
T
T
T
T
T
T
T
T
FUNCTION DESCRIPTION
The address counter indicates the “Display data RAM address”, in which the display data will be transferred and stored.
For the data transmission, once an initial RAM address is determined, the display data can be continuously transmitted
without setting the RAM address each time. When the upper 2 bits (B7 and B6) of the 1st word are “0,0”, the lower 5
bits (B4 to B0) are recognized as RAM address data. And, the 2nd word is recognized as display data, which will be
stored in the RAM address designated by the 1st word, and simultaneously the RAM address is counted up by an
auto-increment operation.
The “Display data RAM address”, which can be specified by the 1
(1D
the 5-bit address counter, and finally the RAM address wraps to “0,0,0,0,0” (00
display data, stored in the RAM address of “1,1,1,1,0” (1E
10
11
12
13
0
1
2
3
4
5
6
7
8
9
H
Character
address
). However, the auto-increment keeps counting up to “1,1,1,1,1” (1F
Recognition data
DISPLAY DATA RAM ADDRESS
C
C
C
C
C
C
C
C
C
C
C
C
C
C
C
10
11
12
13
14
0
1
2
3
4
5
6
7
8
9
B7
0
B7
S
15
B6
0
B6
S
14
B5
S
B5
13
*
S
B4
12
AD4
B4
B3
S
11
Display data RAM address
DISPLAY DATA RAM MAPPING
AD3
B2
S
B3
10
B1
S
AD2
9
B2
*:don’t care
B0
S
8
AD1
B1
0D
1D
RAM
Address
0B
1B
01
03
05
07
09
0F
11
13
15
17
19
1F
H
) and “1,1,1,1,1” (1F
: These display data is ignored.
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
AD0
B0
B7
st
S
7
word, ranges from “0,0,0,0,0” (00
B6
S
6
H
) every display data transmission because of
B5
H
S
H
) and begins counting up. Note that the
5
), is ignored in this sequence.
B4
S
4
B3
S
3
B2
S
2
B1
S
NJU3426
1
H
) to “1,1,1,0,1”
B0
S
0
RAM
Address
00
02
04
06
08
0A
0C
0E
10
12
14
16
18
1A
1C
1E
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
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