PSC Falcon PT40, Руководство по продукции

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Programming Parameters
Product Reference Guide
E-7
Xmodem Protocol
The PT40 supports the Xmodem (checksum) file-transfer protocol for serial
communication, which is available in many commercially marketed products.
Xmodem is a simple send-and-wait-for-response protocol using a fixed-length
data field. The data field is embedded in an Xmodem packet, which also con-
tains a packet number and a single-byte arithmetic checksum. The protocol
link is established by the receiver transmitting a NAK character until the
sender responds. The sender responds by transmitting an Xmodem packet.
The sender then waits for either an ACK signal, in which case it transmits the
next packet, or a NAK signal, in which case it retransmits the packet. Once all
packets are transmitted, the sender transmits an EOT signal, indicating the
end of transmission.
Scan the following bar code to set a PT40 to use the Xmodem protocol:
Save-and-Exit Settings
Table E-4. Save-and-Exit Settings
Xmodem protocol
*$+$-CA02EE*
Setting ID # Type
Save and exit EE Immediate
Exit only, no save EF Immediate
2340.book Page 7 Wednesday, January 29, 2003 12:50 PM