
McQuay Micro Tech Open Protocol Driver Manual
Page 13 of 43
FieldServer Technologies
1991 Tarob Court Milpitas, California 95035 USA
Web
: www.fieldserver.com
Tel
: (408) 262 2299
Fax
: (408) 262 2269
Toll Free
: (888) 509 1970
2
DRIVER FEATURES
When emulating a Client, the driver enables the FieldServer to request ‘Everything’ from the McQuay, allow
specific fields to be read or written and apply device scaling to be applied.
When emulating a Server, the driver provides an emulation of the byte memory of a device and responds to read
and write requests.
The following
important points and limitations
should be noted.
Arising from a feature of the McQuay MicroTech® Open Protocol is the peculiarity that when a multi-byte
value is written to a McQuay device, the write is done one byte at a time (one byte of data can be
transferred per poll/response message pair) allowing for the possibility that the multi byte value is only
partially correct until all the messages have been completed.
The vendor equipment is limited to a maximum of 9600 baud. Given that each message packet can only
transfer one byte of data and that some data of interest is multi-byte, users of this protocol should expect
low data transfer rates.
Port expansion is not supported for this driver.
Each MicroTech® controller is shipped from the factory with a unique job site password. The passwords
are provided by the McQuay International representative at the time of startup.
The driver does not validate passwords when configured as a Server. This means that requests to read or
write data will succeed even if the password supplied with the request is incorrect.
3
DRIVER SCOPE OF SUPPLY
3.1
Supplied by FieldServer Technologies for this driver
FieldServer Technologies Part # Description
FS-8917-16
RJ45 to terminal connector cable.
3.2
Provided by Supplier of 3
rd
Party Equipment
Part # Description
McQuay Motor Mount Connector for Port A connection