Multi-channel vibrating string analog signal acquisition instrument VTN4 16 MODBUS command-driven measurement mode?

When the second and fourth working modes of dip switch are turned on, the equipment works in MODBUS command-driven measuring mode. here

In mode, the equipment is always on and the vibrating wire measurement stops. When the sensor channel data reading of MODBUS protocol is received

When the instruction is taken, the measurement is automatically started, and the instruction packet is read in response to the channel value after the measurement.

Note: This working mode takes effect 30 seconds after the equipment is re-energized.

For example, the VTN device starts with the register 100 as channel data, so it sends and reads the registers between 100 and 163 to the device.

Any register of can start measuring. The following instruction is to send a register read instruction from the register to the device 1.

100, continuously reading 20 registers.

Send to device (16 hexadecimal): 01300 640014041a.

The equipment starts frequency measurement, and after measuring all channels, it responds to the above reading instructions.

Return from the device (16 hexadecimal): 010328 319 000000000000000000000000 0000000 000000 00000 00000 00000 00000 0000 0000 0000 0000 0000 0000 0000 0000 000 0000 0000 0000 000 0000 0000 0000 000

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 34 13 27 0F 27 0F 27 0F 4 1 9E

In the above data:

0x3 1 19 is 1 channel, which is converted into 10, and the radix is 12569, that is, 1256.9Hz.

0x0000 is the second channel, which is converted to 10 as 0.

……

0x34 13 is the 16 channel, which translates into 133 1 that is 1333. 1Hz.