Overview; Communications Specifications - Toshiba RS-485 Operation Manual

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1. Overview

By using RS-485 Option Unit, a network can be constructed that allows communication between a host
computer and multiple ASD units. A maximum of 32 Option Units can be connected on the same
network. And two ASDs can be connected to one Option Unit. A maximum of 64 ASDs can be connected
on the same network. (If ASD has a CPU whose version is V104 or V103, a maximum of 32 ASDs can
be connected on the same network.)
2. Communication specifications
Item
Interface
Configuration
Communication Distance
Connection Points
Number of ASDs per one Option Unit
Number of ASDs on the Same Network
Communication Line Isolation
Synchronization Method
Error Detection Method
Communication Speed
Data Code
Other
Specifications
Conforming to EIA RS485 standard
4-wire, bus type (terminating resistor is necessary at
each end of system)
1,000m maximum
32 units maximum
2 units maximum
64 units maximum (If ASD has a CPU whose version
is V104 or V103, a maximum of 32 ASDs can be
connected on the same network.)
Not isolated
Start-stop synchronization
Parity, checksum
1200/2400/4800/9600 baud selectable (parameter
and switch selection)
ASCII code, binary code
Time-out function available
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