}
for (ch = 0; ch != MAX_CHAR; ch++)
printf(“0x%04x\n”, crctab[ch]);
}
Manually Disabling ECP for Maintenance
Under certain conditions, communications between the host and Encompass 4 Reader may be lost
temporarily and maintenance may be required. The reader or host is sending out a message and waiting
for an acknowledgment. When the acknowledgment is not received, the message is sent again. Additional
messages are also buffered. Often the first indication that the Encompass 4 Reader software is in an ECP
“loop” is when the user/technician sees a recurring display of the same message repeated over and over
again on the monitor. The procedure described in the following paragraphs enables the maintenance
technician to change configuration or test tag reading manually.
Assuming that the ECP timeout is at the factory default of 12.7 seconds (or other value that allows enough
time for the commands to be manually entered) the following command sequence may be used to break
out of an ECP loop. This command sequence uses four ASCII < ` > characters (60 hex) as wild card CRC
values.
Note:
The ASCII <`> character (60 hex) is commonly located on the ~ key.
You must acknowledge existing messages by issuing commands with the generic format:
#x@‘‘‘‘<eom>
where
#
Start-of-message character
x
Message sequence number. This must be the same as the sequence number of the
message being acknowledged
@ A
CK
(acknowledgment character)
<````>
Wild card CRC value for the message
<eom>
End-of-message character
The following is a typical sequence after power-on limiting buffered messages.
Note:
Ensure that no tags are in the field when you are performing this troubleshooting procedure.
Caution
To avoid damage to the Encompass 4 Reader that uses an external antenna, ensure that you
have connected the antenna or a dummy load to the reader before applying power to the
reader.
Encompass 4 Reader System Guide
TransCore Proprietary.
6–84
Summary of Contents for encompass 4
Page 207: ......
