Scaime eNod4-B - 4.8 Continuous Transmission

18/95
User manual SCAIME: NU-soft-eNod4B-E-0716_236704-C.doc
Error code
Meaning
Description
FE
H
unknown command
requested command is not supported by eNod4
FF
H
error during command execution
ex. : tare when gross meas.<0
4.5 Address and Baud rate
Address and baud rate identical to Modbus RTU (See § Modbus RTU)
4.6 Product identification
Product identification identical to Modbus RTU (See § Modbus RTU)
4.7 Measurement transmission
Measurement transmission can be triggered by a master request but it might also be triggered and used through the
following options:
• transmission triggered by a rising or falling edge on a logical input
• transmission at a configurable period (defined in ms) while a logical input is maintained at a given logical
level
• continuous transmission at a configurable period (defined in ms) after a master request. The transmission
is then stopped by another master instruction, be careful not to use this mode in half-duplex at a too high
rate.
4.8 Continuous transmission
SCMBus and fast SCMBus communication protocols allow eNod4 to transmit measurements at a user-defined rate
without the need for successive master queries. To perform this measurement acquisition mode, it is necessary to set
first the ‘sampling period’ (in ms):
Address SCMBus
Description
Accès
Type
0x003F
SCMBus Measurement
transmission period
RW
Uint
A value of 0 implies that measurement transmission is synchronized on the A/N conversion rate. The continuous
transmission is triggered and stopped by reception of the following commands:
SCMBus/fast SCMBus functional command
Command code
start net measurement transmission
E0
H
start factory calibrated points transmission
E1
H
start brut measurement transmission
E2
H
stop continuous transmission
E3
H
Note 1: the measurement transmission rate also depends on the baud rate. So, to achieve the fastest transmission, it
is necessary to use the highest baud rate.
Note 2: as RS485 is a half-duplex communication medium, it can be a little hard to transmit the ‘stop continuous
transmission’ query if the bandwidth is saturated. Therefore, prefer USB communication channel to reach the highest
measurement transmission rate.
4.9 EEPROM error management
EEPROM management identical to Modbus RTU (See § Modbus RTU)