struct.error: pack expected 3 items for packing (got 1)
0
I am trying to implement basic LED ON OFF on 8 Channel USB Relay Card velleman. have found some example code from google and It makes some issuses with packing. Do any one has idea how can I resolve it?
import os
import time
import serial
import subprocess
from struct import pack, unpack, calcsize
ser = serial.Serial(port='COM3', baudrate=9600, stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS, parity=serial.PARITY_NONE)
ser.isOpen()
print(ser)
channel = 0x01
print("RELAY1_ON_COMMAND: 0xFF 0x01 0x01")
state = 0x01
int_msg = [0xFF, channel, state]
print(int_msg)
byte_msg = map(chr, int_msg)
print(byte_msg)
packet = pack('=ccc', b'byte_msg')
print(packet)
ser.write(packet)
time.sleep(1)
print("RELAY1_OFF_COMMAND: 0xFF 0x01 0x00")
state = 0
int_msg = [0xFF, channel, state]
byte_msg = map(chr, int_msg)
packet = pack('=ccc', *byte_msg)
ser.write(packet)
ser.close()
Result:
Traceback (most recent call last):
Serial<id=0x3832fd0, open=True>(port='COM3', baudrate=9600, bytesize=8, parity='N', stopbits=1, timeout=None, xonxoff=False, rtscts=False, dsrdtr=False)
RELAY1_ON_COMMAND: 0xFF 0x01 0x01
[255, 1, 1]
Tests/USBRelayCard.py", line 25, in <module>
<map object at 0x0000000003A94588>
packet = pack('=ccc', b'byte_msg')
struct.error: pack expected 3 items for packing (got 1)
Process finished with exit code 1
python-3.x
asked 21 hours ago
Karthik jyoKarthik jyo
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0
I am trying to implement basic LED ON OFF on 8 Channel USB Relay Card velleman. have found some example code from google and It makes some issuses with packing. Do any one has idea how can I resolve it?
import os
import time
import serial
import subprocess
from struct import pack, unpack, calcsize
ser = serial.Serial(port='COM3', baudrate=9600, stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS, parity=serial.PARITY_NONE)
ser.isOpen()
print(ser)
channel = 0x01
print("RELAY1_ON_COMMAND: 0xFF 0x01 0x01")
state = 0x01
int_msg = [0xFF, channel, state]
print(int_msg)
byte_msg = map(chr, int_msg)
print(byte_msg)
packet = pack('=ccc', b'byte_msg')
print(packet)
ser.write(packet)
time.sleep(1)
print("RELAY1_OFF_COMMAND: 0xFF 0x01 0x00")
state = 0
int_msg = [0xFF, channel, state]
byte_msg = map(chr, int_msg)
packet = pack('=ccc', *byte_msg)
ser.write(packet)
ser.close()
Result:
Traceback (most recent call last):
Serial<id=0x3832fd0, open=True>(port='COM3', baudrate=9600, bytesize=8, parity='N', stopbits=1, timeout=None, xonxoff=False, rtscts=False, dsrdtr=False)
RELAY1_ON_COMMAND: 0xFF 0x01 0x01
[255, 1, 1]
Tests/USBRelayCard.py", line 25, in <module>
<map object at 0x0000000003A94588>
packet = pack('=ccc', b'byte_msg')
struct.error: pack expected 3 items for packing (got 1)
Process finished with exit code 1
python-3.x
asked 21 hours ago
Karthik jyoKarthik jyo
12
New contributor
Karthik jyo is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
0
0
0
I am trying to implement basic LED ON OFF on 8 Channel USB Relay Card velleman. have found some example code from google and It makes some issuses with packing. Do any one has idea how can I resolve it?
import os
import time
import serial
import subprocess
from struct import pack, unpack, calcsize
ser = serial.Serial(port='COM3', baudrate=9600, stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS, parity=serial.PARITY_NONE)
ser.isOpen()
print(ser)
channel = 0x01
print("RELAY1_ON_COMMAND: 0xFF 0x01 0x01")
state = 0x01
int_msg = [0xFF, channel, state]
print(int_msg)
byte_msg = map(chr, int_msg)
print(byte_msg)
packet = pack('=ccc', b'byte_msg')
print(packet)
ser.write(packet)
time.sleep(1)
print("RELAY1_OFF_COMMAND: 0xFF 0x01 0x00")
state = 0
int_msg = [0xFF, channel, state]
byte_msg = map(chr, int_msg)
packet = pack('=ccc', *byte_msg)
ser.write(packet)
ser.close()
Result:
Traceback (most recent call last):
Serial<id=0x3832fd0, open=True>(port='COM3', baudrate=9600, bytesize=8, parity='N', stopbits=1, timeout=None, xonxoff=False, rtscts=False, dsrdtr=False)
RELAY1_ON_COMMAND: 0xFF 0x01 0x01
[255, 1, 1]
Tests/USBRelayCard.py", line 25, in <module>
<map object at 0x0000000003A94588>
packet = pack('=ccc', b'byte_msg')
struct.error: pack expected 3 items for packing (got 1)
Process finished with exit code 1
python-3.x
asked 21 hours ago
Karthik jyoKarthik jyo
12
New contributor
Karthik jyo is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I am trying to implement basic LED ON OFF on 8 Channel USB Relay Card velleman. have found some example code from google and It makes some issuses with packing. Do any one has idea how can I resolve it?
import os
import time
import serial
import subprocess
from struct import pack, unpack, calcsize
ser = serial.Serial(port='COM3', baudrate=9600, stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS, parity=serial.PARITY_NONE)
ser.isOpen()
print(ser)
channel = 0x01
print("RELAY1_ON_COMMAND: 0xFF 0x01 0x01")
state = 0x01
int_msg = [0xFF, channel, state]
print(int_msg)
byte_msg = map(chr, int_msg)
print(byte_msg)
packet = pack('=ccc', b'byte_msg')
print(packet)
ser.write(packet)
time.sleep(1)
print("RELAY1_OFF_COMMAND: 0xFF 0x01 0x00")
state = 0
int_msg = [0xFF, channel, state]
byte_msg = map(chr, int_msg)
packet = pack('=ccc', *byte_msg)
ser.write(packet)
ser.close()
Result:
Traceback (most recent call last):
Serial<id=0x3832fd0, open=True>(port='COM3', baudrate=9600, bytesize=8, parity='N', stopbits=1, timeout=None, xonxoff=False, rtscts=False, dsrdtr=False)
RELAY1_ON_COMMAND: 0xFF 0x01 0x01
[255, 1, 1]
Tests/USBRelayCard.py", line 25, in <module>
<map object at 0x0000000003A94588>
packet = pack('=ccc', b'byte_msg')
struct.error: pack expected 3 items for packing (got 1)
Process finished with exit code 1
python-3.x
python-3.x
asked 21 hours ago
Karthik jyoKarthik jyo
12
New contributor
Karthik jyo is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 21 hours ago
Karthik jyoKarthik jyo
12
New contributor
Karthik jyo is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 21 hours ago
Karthik jyo
asked 21 hours ago
Karthik jyoKarthik jyo
12
New contributor
Karthik jyo is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 21 hours ago
Karthik jyoKarthik jyo
12
asked 21 hours ago
Karthik jyoKarthik jyo
12
12
New contributor
Karthik jyo is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Karthik jyo is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Karthik jyo is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
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