Total Control MP/16, Руководство оператора

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3-12 Using Total Control MIBs
modem modules (which the management module uses for .SDL file
validation). The file transfer begins by transferring the .SDL file in
a series of 512 byte packets. The first packet contains the .SDL file
32-byte header that the management module uses to validate the
software download. If the validation is successful, subsequent
TFTP data packets are transferred.
NOTE
: If a software download fails or is aborted, wait for one
minute before attempting another download. This waiting period
allows the devices to exhaust their timeouts before beginning a
new SDL procedure.
When the TFTP transfer is completed without error, the MS should
poll the uchasCmdCode object in the uchasCmdTable for the slots
involved in the software download. All modules involved in the
software download are erasing their Flash ROM at this time; the
MS must wait until all modules complete this before beginning the
.NAC file transfer. When all slots undergoing software download
have a uchasCmdCode value of downloadingNACFile(82) (i.e., all
modules have successfully erased their Flash), the .NAC file TFTP
transfer may be initiated. The management station must begin the
TFTP transfer of the .NAC file. Failure to do so will result in the
devices aborting the software download.
As an example, the following TFTP command (or its equivalent) is
issued to download the .NAC file to the management module:
TFTP -B PF010000.NAC
192.77.203.65=PF010000.NAC
The first TFTP data packet carries the .NAC file’s header, which the
NMC uses, again, to validate the .NAC file. If the validation
passes, subsequent data packets are sent until the entire .NAC file
is transferred. At this point, the MS may poll the uchasCmdResult
in the uchasCmdTable for the slots involved in the software
download. The success(2) value should be present in these rows.
The NAC software download is complete.
Software Download to the NMC
Software download to the NMC involves a different mechanism
since a large portion of NMC operational code must remain
running in order to support the SDL transport. When instructed to
enter SDL, all other devices use a loader (located in the device’s
Flash ROM boot block), which is in charge of supporting the .SDL
file transfer. In these cases, the operational code is not running on