Rockwell Automation 1395 Multi-Comm Hardware/Software - Manual (Page 41)

Chapter 3
Configuration & Interfacing
3–30
DH+ Communications
Each channel of the MCA board can be configured for Data Highway +
(DH+) communications. Configuration as a DH+ device allows the Drive
to look like a station on the DH+ link. Below is a listing of the DH+
features on this Adapter:
S The Adapter supports 57.6K, 115K, and 230K baud communication
rates.
S Supports Parameter read and parameter write messages for blocks of
parameters.
S A “Token pass with data” mechanism allows fast parameters to be
transferred to other stations along with the network token.
S A method similar to RIO block transfer allows the PLC to issue Drive
messages via DH+.
The DH+ connection to the Drive allows devices such as PLC Controllers
and operator displays to obtain information from the Drive without
burdening the RIO control link.
DH+ Command Set
The MCA board supports a limited set of PCCC commands by emulating a
section of PLC–5 memory. The memory area emulated determines what
specific request and or action the MCA board will take. Below is a list of
the supported commands:
Who Active – The station number of the MCA board (as defined by it’s
DIP switch settings) will be displayed on the “Who Active” screen of the
PLC software. It will read “PLC 5/15 1395” next to the selected station
number.
PLC 5 Typed Read (N10:0–999) – Memory area N10:0–999 translates
into a read parameter value(s) from the Drive. Any attempts to read outside
of this range will result in an error response. The values 0 through 999 are
interpeted by the Drive as parameter numbers. For example, to read the
value of parameter 633 the MSG instruction would request N10:633 with a
size of one element. A size of 10 will write to parameters 633 through 642.
PLC 5 Typed Write (N10:500–999) – Memory area N10:500–999
translates into a write parameter value(s) to the Drive. Any attempts to
write outside of this range will result in an error response. The values 500
through 999 are interpeted by the Drive as parameter numbers. For
example, to write a value to Preset Speed 1 (parameter 633) the MSG
instruction would specify N10:633 with a size of one element. A size of 10
will write to parameters 633 through 642.