70
Checks
Section 1-4
1-4
Checks
All communications errors and recovery from these communication errors
must be processed at the host computer. The E5ZE has the following commu-
nications error detection functions.
Character Check
Vertical Parity Check
The E5ZE in vertical parity check operation checks the exclusive OR of each
character.
Framing Check
The E5ZE determines that there is an error while the E5ZE is communicating
with the host computer if the E5ZE detects a stop bit of 0.
Overrun Check
The E5ZE determines that there is an error while the E5ZE is communicating
with the host computer if the E5ZE processing a character receives the next
character.
Block Check
Format Check
The E5ZE in format check operation checks each command format that the
E5ZE receives.
Numeric Data Check
The E5ZE in numeric data check operation checks the control point numbers
and set values of the E5ZE.
FCS (Frame Check Sequence)
The E5ZE in FCS operation checks the start character @ to the exclusive OR
of the last character in each block.
If there is a communications error which appears to be caused by noise, exe-
cute communications approximately 10 times and check if the communica-
tions error disappears. If communications errors occur frequently, change the
communication speed between the E5ZE and the host computer or use an
optical interface for the transmission path between the E5ZE and host com-
puter.
1-5
Error Processing
If an error occurs in a command block or response block, refer to the following
table to take necessary countermeasures.
Error
Remedy
The end code is not 00.
Check the contents of the end code.
An error code is read.
Check the contents of the error code.
The contents of the response block are
abnormal.
Execute communications again.
No response block returns.
Make sure that the communications con-
ditions of the host computer and E5ZE,
connections between the host computer
the E5ZE, the program used by the host
computer connected to the E5ZE, and
the settings of the E5ZE and host com-
puter are correct.