6
5.2 Signal description
Input and output in this manual are defined as shown above.
Signal level is TTL except for LED lighting.
D0 to D7
：
Bidirectional bus for I/O data.
A0 to A7
：
Address bus, it decodes this signal and select the data of the connected circuit.
HS ENB
：
When this signal is set to High or Open with the data transfer enable signal,
the GP-IB handshake will be usable.
READ
：
It is a strobe signal when reading data of the connection circuit to GP-IB.
WRITE
：
It is a write pulse signal when data from the GP-IB is output to the connection
circuit.
STB1 to 8
：
It is a status signal when SRQ occurs. It will inform the SRQ to the GP-IB
controller.
GP-IB data
HS ENB
RD
Tf
＜
2
μ
s
・
1
Th
≧
0
TRD
3.5
μ
s
≦
TRD
2
3
4
WR(OUT)
：
It sends 1 pulse each time when it is received 1 byte of data from GP-IB.
The device latches the signal of data bus by “WR” signal and “AND” signal of
address signal.
GP-IB data
HS ENB
WR
1
Tdh >
0.25
μ
s
・
TWR
≒
1
・
2
3
4
Tdf > 0.25
μ
s
・
