Hitachi EH-150 Series - Page 144

Chapter 6 Communication mode
6 - 102
Simple data link
 Error in simple data link mode
The detected error in data link operation is separated into two categories, the one is error of EH-SIO and the other is
illegal response from slave station. In case of serious error, data link operation will be stopped. In case of
communication error with slave station, the operation will be continued. The error cause will be indicated in high
byte of status register WXus3. The indicated error code in WXus3 will be cleared by receiving normal response
against the next sending request task code. If error is detected, entry flag of the slave will be off. EH-SIO will sends
a command to all registered slaves. So if a slave replies properly in the next cycle, the slave will come back to the
link network.
Table 6.30 Simple data link mode error
No.
Error
code
Name
Error
level
Detail contents
1
HFF
CPU error
---
EH-SIO operation has been stopped due to the error detection of
CPU module (L.RES ON) was done.
2
---
Watch dog timer
Error
Fatal
Failure
MPU of EH-SIO can’t operate according the system program
anymore, EH-SIO has detected watch dog timer error of MPU.
3
H03
OS system error
Fatal
Failure
EH-SIO has detected an error of system OS.
4
H50
Non-valid command
error
Warning
TRNS 9 command has been used for the port specified as
SLAVE function or simple data link function.
5
H8A
Parity error
Warning
Parity error has been detected in the received data by EH-SIO.
6
H8B
Framing error
Warning
Framing error has been detected in the received data by EH-SIO.
7
H8C
Over run error
Warning
Over run error has been detected in the received data by EH-SIO.
8
H8D
Check code error
Warning
Check code error has been detected in the received data by
EH-SIO.
9
H8E
Receiving timeout error
Warning
EH-SIO could not complete the receive operation within the
specified time.
10
H8F
Sending timeout error
Warning
EH-SIO could not complete the send operation within the
specified time. (the monitoring time interval is fixed and it is not
possible to change this time interval.)
11
H91
Receiving Illegal
message Contents data
Warning
EH-SIO receives message data including illegal data.
« Note »
EH-SIO is checking parity error and framing error in every byte. In case of Hi-Protocol mode, since only the
newest error is indicated, “parity error” and “framing error” can be overwritten by newest error such as “check code
error”. So, if the “check code error” is detected, check also transmit character structure and transmit speed.