Allen-Bradley InView Marquee 2706-P42, User Manual

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Publication 2706-UM016A-EN-P - June 2002
9-12 InView Protocol
InView Display Memory Map
Information transmitted to the displays will write or read information
into holding registers. The holding registers used in the products are
40001 to 40167. Holding registers 40001 to 40103 can be written to.
Registers 40001 to 40100, and 40103 to 40167 can be read from.
The product has three basic areas for registers: 100 registers for
variables, 3 registers for message control, and 64 registers for the
Message Queue. When referencing a holding register, Modbus ASCII
requires that 40001 be subtracted from the holding register address.
For example, when using Priority Messaging, messages are sent to
holding register 40103. The register number that is transmitted would
be (40103-40001=102) or 102 (0x66) would be transmitted at 100
(64h). The following shows the memory map for the Adaptive
Displays:
Methods of Transmission
There are eight different methods of transmission of data to and from
the display. Each one of these use 1 of 4 different Modbus function
codes. Table 9.4 explains each of the four Modbus ASCII function
codes used and Table 9.5 shows the eight methods of using these
codes with the product.
Table 9.3 Memory Map
Modbus Holding Registers Registers Description
40001 001 Variables registers
Variables 001-100 (00-99 with automation
software)
… …
40100 100
40101 101 Add a Message/Downloading of messages
40102 102 Remove a Message
40103 103 Message Queue/Priority Messaging
… …
40167 167