I have a python program that reads serial port and then acting as ModbusTCP server updates Modbus registers. I have a problem with reading Modbus registers with Modbus client, if I set time = 5 # Update delay it doesn't even show values, if I set it to 10 it does update values and I can read them with modbus client, but values are updating too slow.
I do understand the problem. Reading from serial port should be separate function, it should wait for serial port to receive values and then add these values to modbus server registers. While serial port is waiting for values, modbus client should be able to read values already added to modbus server registers.
When LoopingCall calls updating_writer() it executes ser_read_JB1 = ser_JB1.read(386) and I think code just stops there waiting for serial data to be received and while it waits # modbus part is not executed, so modbus client is requesting data, but modbus server is unable to respond.
Code:
import serial
from pymodbus.server.async import StartTcpServer
from pymodbus.server.async import StartUdpServer
from pymodbus.device import ModbusDeviceIdentification
from pymodbus.datastore import ModbusSequentialDataBlock
from pymodbus.datastore import ModbusSlaveContext, ModbusServerContext
from pymodbus.transaction import ModbusRtuFramer, ModbusAsciiFramer
from twisted.internet.task import LoopingCall
import logging
# debug
logging.basicConfig()
log = logging.getLogger()
log.setLevel(logging.DEBUG)
# serial port settings
ser = serial.Serial('COM3', 9600, parity=serial.PARITY_EVEN)
def updating_writer(a):
# serial read part
# JB1 Data
# read the whole package
ser_read_JB1 = ser_JB1.read(386)
# convert ascii to hex
aTOh_JB1 = "".join("{:02x}".format(c) for c in ser_read_JB1)
# convert to string
iTOs_JB1 = str(aTOh_JB1)
# bl_xx_JB1 location of the first byte to read
# from string 2 char = 1 byte
### Momentānā jauda ###
bl_MJ_JB1 = 258
b_konv_MJ_JB1 = (iTOs_JB1[bl_MJ_JB1]+iTOs_JB1[bl_MJ_JB1+1]+
iTOs_JB1[bl_MJ_JB1+2]+iTOs_JB1[bl_MJ_JB1+3])
MJ_JB1 = int(b_konv_MJ_JB1, 16)
### Motorstundas 1. un 2. baits ###
bl_MS_JB1 = 422
b_konv_MS_JB1 = (iTOs_JB1[bl_MS_JB1]+iTOs_JB1[bl_MS_JB1+1]+
iTOs_JB1[bl_MS_JB1+2]+iTOs_JB1[bl_MS_JB1+3])
MS_1_JB1 = int(b_konv_MS_JB1, 16)
### Motorstundas 3. un 4. baits ###
b_konv_MS2_JB1 = (iTOs_JB1[bl_MS_JB1+4]+iTOs_JB1[bl_MS_JB1+5]+
iTOs_JB1[bl_MS_JB1+6]+iTOs_JB1[bl_MS_JB1+7])
MS_2_JB1 = int(b_konv_MS2_JB1, 16)
### Kopējā reaktīvā jauda ###
bl_KRJ_JB1 = 414
b_konv_KRJ_JB1 = (iTOs_JB1[bl_KRJ_JB1]+iTOs_JB1[bl_KRJ_JB1+1]+
iTOs_JB1[bl_KRJ_JB1+2]+iTOs_JB1[bl_KRJ_JB1+3])
KRJ_JB1 = int(b_konv_KRJ_JB1, 16)
### Kopējā aktiva jauda 1. 2. baits ###
bl_KAJ_1_JB1 = 402
b_konv_KAJ_1_JB1 = (iTOs_JB1[bl_KAJ_1_JB1]+iTOs_JB1[bl_KAJ_1_JB1+1]+
iTOs_JB1[bl_KAJ_1_JB1+2]+iTOs_JB1[bl_KAJ_1_JB1+3])
KAJ_1_JB1 = int(b_konv_KAJ_1_JB1, 16)
### Kop aktiva jauda 3. 4. baits ##
b_konv_KAJ_2_JB1 = (iTOs_JB1[bl_KAJ_1_JB1+4]+iTOs_JB1[bl_KAJ_1_JB1+5]+
iTOs_JB1[bl_KAJ_1_JB1+6]+iTOs_JB1[bl_KAJ_1_JB1+7])
KAJ_2_JB1 = int(b_konv_KAJ_2_JB1, 16)
### P Jacket Water (bar) ###
bl_PJW_JB1 = 266
b_konv_PJW_JB1 = (iTOs_JB1[bl_PJW_JB1]+iTOs_JB1[bl_PJW_JB1+1]+
iTOs_JB1[bl_PJW_JB1+2]+iTOs_JB1[bl_PJW_JB1+3])
PJW_JB1 = int(b_konv_PJW_JB1, 16)
### P oil ###
bl_POIL_JB1 = 274
b_konv_POIL_JB1 = (iTOs_JB1[bl_POIL_JB1]+iTOs_JB1[bl_POIL_JB1+1]+
iTOs_JB1[bl_POIL_JB1+2]+iTOs_JB1[bl_POIL_JB1+3])
POIL_JB1 = int(b_konv_POIL_JB1, 16)
### T Oil C2 (temp) ###
bl_TOIL_JB1 = 270
b_konv_TOIL_JB1 = (iTOs_JB1[bl_TOIL_JB1]+iTOs_JB1[bl_TOIL_JB1+1]+
iTOs_JB1[bl_TOIL_JB1+2]+iTOs_JB1[bl_TOIL_JB1+3])
TOIL_JB1 = int(b_konv_TOIL_JB1, 16)
### Turbo bypass CTR1 2. v stav ###
bl_TBP_JB1 = 558
b_konv_TBP_JB1 = (iTOs_JB1[bl_TBP_JB1]+iTOs_JB1[bl_TBP_JB1+1]+
iTOs_JB1[bl_TBP_JB1+2]+iTOs_JB1[bl_TBP_JB1+3])
TBP_JB1 = int(b_konv_TBP_JB1, 16)
### Ainara A L1 ###
bl_AAL1_JB1 = 530
b_konv_AAL1_JB1 = (iTOs_JB1[bl_AAL1_JB1]+iTOs_JB1[bl_AAL1_JB1+1]+
iTOs_JB1[bl_AAL1_JB1+2]+iTOs_JB1[bl_AAL1_JB1+3])
AAL1_JB1 = int(b_konv_AAL1_JB1, 16)
### Ainara A L2 ###
bl_AAL2_JB1 = 534
b_konv_AAL2_JB1 = (iTOs_JB1[bl_AAL2_JB1]+iTOs_JB1[bl_AAL2_JB1+1]+
iTOs_JB1[bl_AAL2_JB1+2]+iTOs_JB1[bl_AAL2_JB1+3])
AAL2_JB1 = int(b_konv_AAL2_JB1, 16)
### Ainara A L3 ###
bl_AAL3_JB1 = 538
b_konv_AAL3_JB1 = (iTOs_JB1[bl_AAL3_JB1]+iTOs_JB1[bl_AAL3_JB1+1]+
iTOs_JB1[bl_AAL3_JB1+2]+iTOs_JB1[bl_AAL3_JB1+3])
AAL3_JB1 = int(b_konv_AAL3_JB1, 16)
### 1. Cilindra temp. ###
bl_CIL1_JB1 = 322
b_konv_CIL1_JB1 = (iTOs_JB1[bl_CIL1_JB1]+iTOs_JB1[bl_CIL1_JB1+1]+
iTOs_JB1[bl_CIL1_JB1+2]+iTOs_JB1[bl_CIL1_JB1+3])
CIL1_JB1 = int(b_konv_CIL1_JB1, 16)
### 2. Cilindra temp. ###
bl_CIL2_JB1 = 326
b_konv_CIL2_JB1 = (iTOs_JB1[bl_CIL2_JB1]+iTOs_JB1[bl_CIL2_JB1+1]+
iTOs_JB1[bl_CIL2_JB1+2]+iTOs_JB1[bl_CIL2_JB1+3])
CIL2_JB1 = int(b_konv_CIL2_JB1, 16)
### 3. Cilindra temp. ###
bl_CIL3_JB1 = 330
b_konv_CIL3_JB1 = (iTOs_JB1[bl_CIL3_JB1]+iTOs_JB1[bl_CIL3_JB1+1]+
iTOs_JB1[bl_CIL1_JB3+2]+iTOs_JB1[bl_CIL3_JB1+3])
CIL3_JB1 = int(b_konv_CIL3_JB1, 16)
### 4. Cilindra temp. ###
bl_CIL4_JB1 = 334
b_konv_CIL4_JB1 = (iTOs_JB1[bl_CIL4_JB1]+iTOs_JB1[bl_CIL4_JB1+1]+
iTOs_JB1[bl_CIL1_JB4+2]+iTOs_JB1[bl_CIL4_JB1+3])
CIL4_JB1 = int(b_konv_CIL4_JB1, 16)
### 5. Cilindra temp. ###
bl_CIL5_JB1 = 338
b_konv_CIL5_JB1 = (iTOs_JB1[bl_CIL5_JB1]+iTOs_JB1[bl_CIL5_JB1+1]+
iTOs_JB1[bl_CIL5_JB1+2]+iTOs_JB1[bl_CIL5_JB1+3])
CIL5_JB1 = int(b_konv_CIL5_JB1, 16)
### 6. Cilindra temp. ###
bl_CIL6_JB1 = 342
b_konv_CIL6_JB1 = (iTOs_JB1[bl_CIL6_JB1]+iTOs_JB1[bl_CIL6_JB1+1]+
iTOs_JB1[bl_CIL6_JB1+2]+iTOs_JB1[bl_CIL6_JB1+3])
CIL6_JB1 = int(b_konv_CIL6_JB1, 16)
### 7. Cilindra temp. ###
bl_CIL7_JB1 = 346
b_konv_CIL7_JB1 = (iTOs_JB1[bl_CIL7_JB1]+iTOs_JB1[bl_CIL7_JB1+1]+
iTOs_JB1[bl_CIL7_JB1+2]+iTOs_JB1[bl_CIL7_JB1+3])
CIL7_JB1 = int(b_konv_CIL7_JB1, 16)
### 8. Cilindra temp. ###
bl_CIL8_JB1 = 350
b_konv_CIL8_JB1 = (iTOs_JB1[bl_CIL8_JB1]+iTOs_JB1[bl_CIL8_JB1+1]+
iTOs_JB1[bl_CIL8_JB1+2]+iTOs_JB1[bl_CIL8_JB1+3])
CIL8_JB1 = int(b_konv_CIL8_JB1, 16)
### 9. Cilindra temp. ###
bl_CIL9_JB1 = 354
b_konv_CIL9_JB1 = (iTOs_JB1[bl_CIL9_JB1]+iTOs_JB1[bl_CIL9_JB1+1]+
iTOs_JB1[bl_CIL9_JB1+2]+iTOs_JB1[bl_CIL9_JB1+3])
CIL9_JB1 = int(b_konv_CIL9_JB1, 16)
### 10. Cilindra temp. ###
bl_CIL10_JB1 = 358
b_konv_CIL10_JB1 = (iTOs_JB1[bl_CIL10_JB1]+iTOs_JB1[bl_CIL10_JB1+1]+
iTOs_JB1[bl_CIL10_JB1+2]+iTOs_JB1[bl_CIL10_JB1+3])
CIL10_JB1 = int(b_konv_CIL10_JB1, 16)
### 11. Cilindra temp. ###
bl_CIL11_JB1 = 362
b_konv_CIL11_JB1 = (iTOs_JB1[bl_CIL11_JB1]+iTOs_JB1[bl_CIL11_JB1+1]+
iTOs_JB1[bl_CIL11_JB1+2]+iTOs_JB1[bl_CIL11_JB1+3])
CIL11_JB1 = int(b_konv_CIL11_JB1, 16)
### 12. Cilindra temp. ###
bl_CIL12_JB1 = 366
b_konv_CIL12_JB1 = (iTOs_JB1[bl_CIL12_JB1]+iTOs_JB1[bl_CIL12_JB1+1]+
iTOs_JB1[bl_CIL12_JB1+2]+iTOs_JB1[bl_CIL12_JB1+3])
CIL12_JB1 = int(b_konv_CIL12_JB1, 16)
### 13. Cilindra temp. ###
bl_CIL13_JB1 = 370
b_konv_CIL13_JB1 = (iTOs_JB1[bl_CIL13_JB1]+iTOs_JB1[bl_CIL13_JB1+1]+
iTOs_JB1[bl_CIL13_JB1+2]+iTOs_JB1[bl_CIL13_JB1+3])
CIL13_JB1 = int(b_konv_CIL13_JB1, 16)
### 14. Cilindra temp. ###
bl_CIL14_JB1 = 374
b_konv_CIL14_JB1 = (iTOs_JB1[bl_CIL14_JB1]+iTOs_JB1[bl_CIL14_JB1+1]+
iTOs_JB1[bl_CIL14_JB1+2]+iTOs_JB1[bl_CIL14_JB1+3])
CIL14_JB1 = int(b_konv_CIL14_JB1, 16)
### 15. Cilindra temp. ###
bl_CIL15_JB1 = 378
b_konv_CIL15_JB1 = (iTOs_JB1[bl_CIL15_JB1]+iTOs_JB1[bl_CIL15_JB1+1]+
iTOs_JB1[bl_CIL15_JB1+2]+iTOs_JB1[bl_CIL15_JB1+3])
CIL15_JB1 = int(b_konv_CIL15_JB1, 16)
### 16. Cilindra temp. ###
bl_CIL16_JB1 = 382
b_konv_CIL16_JB1 = (iTOs_JB1[bl_CIL16_JB1]+iTOs_JB1[bl_CIL16_JB1+1]+
iTOs_JB1[bl_CIL16_JB1+2]+iTOs_JB1[bl_CIL16_JB1+3])
CIL16_JB1 = int(b_konv_CIL16_JB1, 16)
### 17. Cilindra temp. ###
bl_CIL17_JB1 = 386
b_konv_CIL17_JB1 = (iTOs_JB1[bl_CIL17_JB1]+iTOs_JB1[bl_CIL17_JB1+1]+
iTOs_JB1[bl_CIL17_JB1+2]+iTOs_JB1[bl_CIL17_JB1+3])
CIL17_JB1 = int(b_konv_CIL17_JB1, 16)
### 18. Cilindra temp. ###
bl_CIL18_JB1 = 390
b_konv_CIL18_JB1 = (iTOs_JB1[bl_CIL18_JB1]+iTOs_JB1[bl_CIL18_JB1+1]+
iTOs_JB1[bl_CIL18_JB1+2]+iTOs_JB1[bl_CIL18_JB1+3])
CIL18_JB1 = int(b_konv_CIL18_JB1, 16)
### 19. Cilindra temp. ###
bl_CIL19_JB1 = 394
b_konv_CIL19_JB1 = (iTOs_JB1[bl_CIL19_JB1]+iTOs_JB1[bl_CIL19_JB1+1]+
iTOs_JB1[bl_CIL19_JB1+2]+iTOs_JB1[bl_CIL19_JB1+3])
CIL19_JB1 = int(b_konv_CIL19_JB1, 16)
### 20. Cilindra temp. ###
bl_CIL20_JB1 = 398
b_konv_CIL20_JB1 = (iTOs_JB1[bl_CIL20_JB1]+iTOs_JB1[bl_CIL20_JB1+1]+
iTOs_JB1[bl_CIL20_JB1+2]+iTOs_JB1[bl_CIL20_JB1+3])
CIL20_JB1 = int(b_konv_CIL20_JB1, 16)
### C1 (temp) ###
#bl_C1_JB1 = 262
#b_konv_C1_JB1 = (iTOs_JB1[bl_C1_JB1]+iTOs_JB1[bl_C1_JB1+1]+
# iTOs_JB1[bl_C1_JB1+2]+iTOs_JB1[bl_C1_JB1+3])
#C1_JB1 = int(b_konv_C1_JB1, 16)
# modbus part
log.debug("updating the context")
context = a[0]
register = 0x03
slave_id = 0x01
address = 0x01
values = context[slave_id].getValues(register, address, count=33)
values = [
MJ_JB1, MS_1_JB1 ,MS_2_JB1, KRJ_JB1, KAJ_1_JB1, KAJ_2_JB1,
PJW_JB1, POIL_JB1, TOIL_JB1, TBP_JB1, AAL1_JB1, AAL2_JB1,
AAL3_JB1, CIL1_JB1, CIL2_JB1, CIL3_JB1, CIL4_JB1, CIL5_JB1,
CIL6_JB1, CIL7_JB1, CIL8_JB1, CIL9_JB1, CIL10_JB1, CIL11_JB1,
CIL12_JB1, CIL13_JB1, CIL14_JB1, CIL15_JB1, CIL16_JB1, CIL17_JB1,
CIL18_JB1, CIL19_JB1, CIL20_JB1
]
log.debug("new values: " + str(values))
context[slave_id].setValues(register, address, values)
def run_updating_server():
store = ModbusSlaveContext(
di = ModbusSequentialDataBlock(0, [0]*1),
co = ModbusSequentialDataBlock(0, [0]*1),
hr = ModbusSequentialDataBlock(0, [33]*1),
ir = ModbusSequentialDataBlock(0, [0]*1))
context = ModbusServerContext(slaves=store, single=True)
identity = ModbusDeviceIdentification()
identity.VendorName = 'pymodbus'
identity.ProductCode = 'PM'
identity.VendorUrl = 'http://github.com/bashwork/pymodbus/'
identity.ProductName = 'pymodbus Server'
identity.ModelName = 'pymodbus Server'
identity.MajorMinorRevision = '1.0'
time = 5 # Update delay
loop = LoopingCall(f=updating_writer, a=(context,))
loop.start(time, now=True)
StartTcpServer(context, identity=identity, address=("10.10.10.253", 502))
if __name__ == "__main__":
run_updating_server()
