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IM9000F02-E2
4. RKC STANDARD COMMUNICATION
4.1 Communication protocol
The REX-F9000 uses the polling/selecting method to establish a data link. The basic procedure is
followed ANSI X3.28 subcategory 2.5, A4 basic mode data transmission control procedure (Fast
selecting is established for selecting).
z
In the polling/selecting method, the REX-F9000 is controlled completely by the host computer
is permitted. Since the host computer invites information message sending from and receiving
to the REX-F9000, send the data in accordance with the polling or selecting procedure.
(Centralized control method)
z
The code use in communication is 7-bit ASCII code including transmission control character.
The transmission control characters are [EOT] (04H), [ENQ] (05H), [ACK] (06H), [NAK]
(15H), [STX] (02H) and [ETX] (03H). The figure in the parenthesis is indicating hexadecimal
number.
4.1.1 Polling
Polling is an action that host computer requesting one of the REX-F9000 which selected among
multidrop connected, to transmit the data. The procedure is as the following.
Host
computer
send
Host
computer
send
Host computer send
REX-F9000
send
REX-F9000 send
E
O
T
E
O
T
[ Data ]
[ BCC ]
[ ID ]
(1)
(2)
(5)
(3)
(4)
(9)
(7)
(10)
[Address] [ ID ]
No response
No
response
Indefinite
Time
out
ID: Identifier
E
O
T
E
O
T
S
T
X
A
C
K
N
A
K
E
T
X
E
N
Q
(8)
(6)
