Omron TJ2-MC64 - PROGRAMMING Programming Manual page 221

Communication protocols
End code Description Probable cause
$14 Format error •
•
•
$15 Entry number The data is outside the specified
data error range or too long.
$18 Frame length The maximum frame length of
error 131 bytes is exceeded.
$19 Not executable You did not obtain access rights.
$21 Not executable The command cannot be exe-
due to CPU cuted because a CPU error has
error. occurred.
$100 Host Link slave -
ACK timeout
$200 IC command -
address error
Set up
You need the SETCOM command to set up the serial port of the TJ2-MC64
for the Host Link Master protocol. Set the command as follows:
SETCOM(baudrate, data_bits, stop_bits, parity, port, 6)
After you have set this command, you can use the HLM_READ,
HLM_WRITE and HLM_COMMAND commands to read and write data
using Host Link.
PROGRAMMING MANUAL
Solution
The command format is Check the format and
wrong. transfer the command
A command that cannot be again.
divided has been divided.
The frame length is smaller
than the minimum length for
the applicable command.
Correct the command
arguments and trans-
fer the command
again.
Check the command
and transfer the com-
mand again.
Obtain access rights.
Cycle the power sup-
ply of the CPU.
-
-
Timeout
The timeout mechanism is implemented to prevent that the BASIC task
pauses for a long time due to bad or no communication. The
HLM_TIMEOUT parameter specifies the timeout period. This period is the
maximum time the program task waits after it has sent the command to
receive a response.
If the timeout period elapses, the HLM_STATUS contains the status of the
command, and the BASIC task continues.
The HLM_TIMEOUT parameter specifies the timeout period for all
commands and for all ports.
Status
The HLM_STATUS parameter contains the status of the last Host Link
master command sent to the specified port. The parameter indicates the
status for the HLM_READ, HLM_WRITE and HLM_COMMAND
commands. The status bits are:
/i
Bit Name Description
0-7 End code The end code is:
• the end code defined by the Host Link slave, when a prob-
lem occurred in the data string of the sent command, or
• an end code defined by the Host Link master, when a prob-
lem occurred in the data string of the received response.
8 Timeout error A timeout error occurs if no response is received within the time-
out period. This indicates that the communication is lost.
9 Command not This status indicates that the slave did not recognise the com-
recognised mand and has returned an IC response.
The HLM_STATUS has value 0 when no problems occurred. In case of a
non-zero value you need to program an appropriate action such as a retry or
emergency stop in the user BASIC program. Each port has an
HLM_STATUS parameter. You need the PORT modifier to specify the port.
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