Overview - Hitachi 902 Service Manual

16. SYSTEM INTERFACE
16.1

Overview

Provided here are the signal form and protocol (communication rules) in case of connection
between the Model 902 and an external system (hereafter referred to as a host) via
asynchronous serial signal.
(1) Specifications of Communication
The following table lists the specifications of RS-232C communication.
No. Item
1 Interface
2 Communication
method
3 Data bit
4 Stop bit
5 Parity check
6 Baud rate (bit/sec)
7 Max. volume of
transferred data
8 End-of-data code
9 Code
10 Synchronization
system
11 Transmission
control procedure
12 Number of ports
13 Text mode
14 Cable length
(2) Features
(a) The communication cycle is not synchronized with the analysis cycle. So the
analyzer replies upon receiving a response from the host.
(b) The data bit, stop bit, parity check, baud rate, maximum volume of transferred data
and end-of-data code are selectable by the user.
Table 16-1 Specifications of Communication
Specifications
RS-232C or 20 mA current
loop
Half duplex
7 or 8 bits
1 bit/2 bits
Even/odd/no parity
NOTE
4800/9600
256/512 bytes
ETX + BCC/CR + LF +
ETX/ETX
ETX + CR + LF
ETX + CKSH + CKSL + CR
JIS 7 bits, JIS 8 bits or ASCII
Asynchronous system
(Start-stop transmission)
Determined by host
1 max.
Nontransparent mode (ASCII)
15 m max. (RS-232C)
Remarks
Communication
parameter screen
16 - 1
Default Value
(standard value)
 
 
7 bits
2 bits
Even parity
9600
256
ETX + BCC





