TransCore SmartPass AI1611, System Manual

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General Software Information
Boot Failure Message
The software performs a checksum function on itself. The function returns a specific
value for the particular version of software. If the value returned is not correct, the
boot ROM checksum assumes that locations have been corrupted, and a failure
condition exists. If the boot ROM checksum is not correct, a boot failure message is
transmitted. If the failure message does not transmit, a communications error has
occurred or the boot failed to the extent that it cannot transmit the failure message.
Tag/Message Buffer
SmartPass readers maintain a tag buffer in battery-backed RAM to save tag IDs
acquired while in the command mode or buffer control mode and when data inquiry
protocol is used. This buffer holds up to 195 time- stamped messages. Error
messages will be transmitted to the host to provide buffer status as it fills. When the
buffer fills, subsequent tag IDs will be lost. For more information on how the buffer
works, refer to the
Error Messages
section in this chapter.
Time and Date
The time and date can be appended to tag ID strings, error messages, presence
without tag reports, and input status change reports. A real-time clock maintains the
current date and time. This clock can be set using host commands 20 and 21. The
date and time can be displayed using command 22.
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