An electronic shelf label (ESL) system with register corrections is
described. An ESL includes a plurality of registers for storing
information controlling the content and formatting of information. A host
computer system includes an ESL data file comprising a data image of the
ESL's registers. The host computer calculates one or more sumchecks of the
data image, and transmits one or more bedcheck messages including the
sumchecks to the ESL. The ESL receives each bedcheck message and compares
each received sumcheck with a sumcheck calculated using the information
stored in the ESL's registers. If the received sumcheck matches the
calculated sumcheck, the ESL transmits a positive acknowledgement message
to the host computer. Otherwise, the ESL transmits a negative
acknowledgment message to the host computer. The host computer then
transmits a series of messages to the ESL updating the plurality of
registers with the data image.
