100/180 mm PAPERLESS GRAPHIC RECORDER: USER GUIDE
HA028910
Issue 13 Sep 16
User Guide
Page 316
8.4.5 Feature identifi cation table ( FIT)
This table allows the host to identify which features are available at the recorder.
Number of features
Number of supported features
3
Read only CC26 (52262)
1
Feature 1
Indirection Table
1
Read only CC27 (52263)
1
Read only indirection table start address (R/O vector)
CD89
Read only CC28 (52264)
1
Read/Write indirection table start address (R/W vector)
D18A
Read only CC29 (52265)
1
Spare
CC2A (52266)
1
Feature 2
Function codes supported (FC I.D.)
4
Read only CC2B (52267)
1
Bit map of supported MODBUS function codes
32940
Read only CC2C (52268)
1
Bit 0: 0 = code 1 not supported; 1 = code 1 supported
Bit 1: 0 = code 2 not supported; 1 = code 2 supported
Bit 2: 0 = code 3 not supported; 1 = code 3 supported
Bit 3: 0 = code 4 not supported; 1 = code 4 supported
Etc.
Bit 15: 0 = code 16 not supported; 1 = code 16 supported
Reserved
CC2D (52269)
1
Reserved
CC2E (52270)
1
Feature 3
Security ID (MODBUS login security feature)
9
Read only CC2F (52271)
1
User name
Write only CC30 (52272)
40
Password
Write only CC58 (52312)
40
Reserved
CC80 (52352)
1
Feature N
100 Spare addresses for further features
CC81 (52353)
100
8.4.6 Indirection tables
The standard MODBUS protocol allows block register reads and writes. This is effi cient only if data is
grouped contiguously, or nearly so. Indirection tables are a means by which widely spaced register ad-
dresses can (in effect) be grouped, offering the host the ability to access a block of user defi ned data in
one single read/write request.
Two confi gurable tables are available, one for read only parameters, the other for read/write.
Each table
is in two halves - the lower address half contains the addresses of the registers to be accessed; the higher
address half contains the values which have been read or which are to be written.
Notes:
1. For Ethernet connections, indirection table entries are lost at power off, as the result of a
brown-out or if the connection with the host is broken.
2. Parameters in IEEE format can be accessed by confi guring two successive entries in the table.
Parameters which occupy more than one register can be loaded into the indirection area by
using function code 16 (pre-set multiple registers) and the parameter’s base address (i.e. the
parameter’s 1st register).
3. Separate indirection table entries are held for each host - the recorder automatically switches
each host to its own indirection table without user intervention.
4. Indirection table addresses (CCE5 to D4E7) cannot be entered in the indirection tables. Any
attempt to do so will be ignored.
Parameter
Description
Value
Access
Start Addr. Register
Name
Hex (Dec)
Length
