CV500BSC51 Omron, CV500BSC51 Datasheet - Page 82

• Manufacturer Part Number: CV500BSC51
• Description: Programmable Logic Controller
• Manufacturer: Omron

Specifications of CV500BSC51

• Peak Reflow Compatible (260 C): No
• Leaded Process Compatible: No
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

7-3
Other Communications Problems
The byte order is reversed in
the received data.
Only part of the expected data
can be received.
More data than expected was
received.
(There is incorrect data at the
end of the received data.)
The received data was over-
written by new data before it
could be read by IORD(222).
The data received at the host
computer (or other device) is
garbled.
Other Communications Problems
---
The GP-IB Interface Unit is the receiving
device and allocated CIO word n+6 (num-
ber of data bytes received) indicates that
the Unit received the expected number of
bytes.
The GP-IB Interface Unit is the receiving
device and allocated CIO word n+6 (num-
ber of data bytes received) indicates that
the Unit received less data than expected.
The GP-IB Interface Unit is the transmitting
device.
The GP-IB Interface Unit is the receiving
device and allocated CIO word n+6 (num-
ber of data bytes received) indicates that
the Unit received the expected number of
bytes.
The GP-IB Interface Unit is the transmitting
device.
The GP-IB Interface Unit is operating in
Slave mode.
The enhanced BASIC commands function
is being used.
Problem
Check the “data storage order” setting in
the allocated DM area words (bits 00 to 07
of m+1) and change it if necessary.
The “number of words to transfer” setting in
the IORD(222) operand is less than the
number of words received by the Unit.
Check the “number of data bytes received”
value in n+6 and set the IORD(222) oper-
and correctly.
A single IORD(222) instruction can read up
to 128 words of data. Two or more
IORD(222) instructions must be executed if
more than 128 words have been received.
Refer to 4-4-3 Reading more than 128
Words for more details.
When binary data is being transferred, it is
possible that the data accidentally con-
tained the delimiter code. Set the system so
that reception is completed when the EOI
signal is detected.
Check whether the “number of bytes to
receive” setting in the allocated DM area
word (m+5) is less than the actual number
of bytes being transferred. Change the set-
ting if necessary.
The number of bytes of transmission data in
buffer memory is less than planned. Set the
“number of words to transfer” operand cor-
rectly in IOWR(223).
The “number of words to transfer” setting in
the IORD(222) operand is greater than the
number of words received by the Unit.
Check the “number of data bytes received”
value in n+6 and set the IORD(222) oper-
and correctly.
The number of bytes of transmission data in
buffer memory is greater than planned. Set
the “number of words to transfer” operand
correctly in IOWR(223).
The number of bytes of transmission data
written to the transmission data buffer by
IOWR(223) is less than planned. Set the
transmission data correctly with
IOWR(223).
After the Data Read Completed Flag went
ON, the IORD(222) instruction read data
from the wrong part of buffer memory.
Verify that IORD(222) is reading from the
buffer memory’s reception data area after
the Data Read Completed Flag goes ON.
The Unit is able to receive more data only
after the Data Read Completed Flag is
turned OFF by executing IORD(222).
Data is being transferred in binary mode.
Execute the ID0 or OD0 command so that
the Unit converts binary data to ASCII.
Probable cause and remedy
Section 7-3
65