Fema B Series, User Manual, Page: 12 / 36

FEMA ELECTRÓNICA . SERIES B . Models Bxx-RTU
12
1.17 Registers and functions : 16 bits ‘Process slave’
List of available registers (see Table 14) and available func -
tions
(see Table 15)
for instruments configured in ‘Process
slave’ mode and 16 bits data length.
• accessing a function not listed in the table, returns error
1 ‘Illegal Function’.
• accessing a register not listed in the table, returns error 2
‘Illegal Data Address’.
• working with 16 bit registers allows for codification of
numbers between 32767 and -32767. To work with num -
bers up to 999999 / -199999, configure registers for 32 bits
data
(see section 1.21.5).
• registers Setpoint 1, Setpoint 2 and Setpoint 3 are dis -
abled by default (setpoint value is modified through the
front keypad). To enable access to read and write these
registers through the bus, while staying in ‘Process slave’
mode, see section 1.21.14.
- writing to the setpoint registers when they are disabled
returns error 2 ‘Illegal Data Address’.
- modifying a setpoint value manually from the front key
-
pad, does not update the value stored at the setpoint
register. Reading the setpoint register does not access the
setpoint value configured in the instrument, but the last
written value on the register.
• after power loss, the instrument starts up with all regis
-
ters initialized to ‘0’
(see section 1.16).
• the ‘Resolution’ register contains a numerical value indi -
cating the number of decimal places on display. Valid val -
ues from 0 to 5. Writing value 2 lights the decimal point at
position XXXX.XX. Non valid values are discarded and no
error message is generated.
• all registers are read and write registers.
• access to reserved registers does not generate error mes
-
sages.
Example - to update the display of the instrument to a value
of 432.1, write onto ‘Display’ register the number ‘4321’ and
write onto ‘Resolution’ register the number ‘1’.
Register ‘Display’ : ‘4321’
Register ‘Resolution’ : ‘1’
Register number Name
0 Display
1 Resolution
2 Setpoint 1*
3 Setpoint 2*
4 Setpoint 3*
5 Reserved
Table 14 - Registers in 16 bits and ‘Process slave’ mode
Function number Name
6 Write single register
16 Write multiple registers
3 Read registers
Table 15 - Functions in 16 bits and ‘Process slave’ mode