Hitachi 902 - Overview

16 - 1
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.
Table 16-1 Specifications of Communication
No. Item Specifications Remarks
Default Value
(standard value)
1 Interface RS-232C or 20 mA current
loop
 
2 Communication
method
Half duplex  
3 Data bit 7 or 8 bits
Communication
7 bits
4 Stop bit 1 bit/2 bits
parameter screen
2 bits
5 Parity check Even/odd/no parity Even parity
6 Baud rate (bit/sec) 4800/9600
NOTE
9600
7 Max. volume of
transferred data
256/512 bytes 256
8 End-of-data code ETX + BCC/CR + LF +
ETX/ETX
ETX + CR + LF
ETX + CKSH + CKSL + CR
ETX + BCC
9 Code JIS 7 bits, JIS 8 bits or ASCII 
10 Synchronization
system
Asynchronous system
(Start-stop transmission)

11 Transmission
control procedure
Determined by host 
12 Number of ports 1 max. 
13 Text mode Nontransparent mode (ASCII) 
14 Cable length 15 m max. (RS-232C) 
(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.