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Manual -MD150T – 27.10.2014 – v.1.3
page 12
Map of MD150T records
Address
Name
Variable type
Mode(Modbus
function)
Description
0 -1 (*1-2)
MES_DINT
DINT
R (0x03)
Measurement value (only complete part)
2 -3 (*3-4)
MES_MIN_DINT
DINT
R (0x03)
Registered minimal value (only complete
part)
4 -5 (*5-6)
MES_MAX_DINT
DINT
R (0x03)
Registered maximal value (only complete
part)
6 -7 (*7-8)
MES_REAL
REAL
R (0x03)
Measurement value (floating point)
8 -9 (*9-10)
MES_MIN_REAL
REAL
R (0x03)
Registered minimal value (floating point)
10 -11 (*11-12)
MES_MAX_REAL
REAL
R (0x03)
Registered maximal value (floating point)
5000 (*5001)
TARA
BYTE
W (0x05)
Reset of sensor indications.
5002 (*5003)
PK_OUT
BYTE
R (0x01)
Reading of relay outputs status
(bit 0:PK1, bit 1:PK2)
4000 (*4001)
INPUTS
BYTE
R (0x01)
Reading of inputs status
(bit 0: TARA. bit 1: DIN2)
*
for devices with address starting with
1 value(offset a1)
R – reading register, W - record
CAUTION: 4-Byte number of type REAL is contained in two registries. The first registry contains younger part of the number,
the second - its older part. In order to read REAL number value correctly, read registries of number 2 and 3 and then
conduct appropriate conversion.
Conversion of 2 registries (4 Byte) into 32 Bit number REAL
Registry_2 HI <-> Byte1
Registry_2 LO <-> Byte0
Registry_3 HI <-> Byte3
Registry_3 LO <-> Byte2
Number _32_bit = Byte3<<24 + Byte2<<16 + Byte1<<8 + Byte0
Or number_32_bit = Regi Registry_3<<16
For DINT registers, if measurement result is within range -32768 up to 32767 reading of first register
is enough.
Example of MODBUS communication table
Reading of measurement (DINT value) – MES_DINT (
Function: 03,
Registry address: 0
)
Request (MODBUS MASTER -> MD150T)
Response (MD150T -> MODBUS MASTER)
Device address
0x01
Device address
0x01
Function
0x03
Function
0x03
Hi registry address
0x00
Byte number
0x04
Lo registry address
0x00
Registry 0x02 Hi
REAL (Byte1)
Number of Hi registries
0x00
Registry 0x02 Lo
REAL (Byte 0)
Number of Lo registries
0x02
Registry 0x03 Hi
REAL ( Byte 3)
CRC Hi
0xC4
Registry 0x03 Lo
REAL (Byte 2)
CRC Lo
0x0B
CRC Hi
8 bit
CRC Lo
8 bit
Reset of digital processing unit -
TARA
(
Function: 05,
Registry address: 5000
)
Request (MODBUS MASTER -> MD150T)
Response (MD150T) -> MODBUS MASTER)
Device address
0x01
Device address
0x01
Function
0x05
Function
0x05
Address of Hi registries
0x13
Address of Hi registries
0x13
Address of Lo registries
0x88
Address of Lo registries
0x88
Registry 0x00 Hi
0xFF
Registry0x00 Hi
0xFF
Registry 0x00 Lo
0x00
Registry0x00 Lo
0x00
CRC
16 Bytes
CRC
16
Bytes
