User's Manual

Table Of Contents
Remote Firmware Update
AT+i Programmer‘s Manual Version 8.32 25-1
25 Remote Firmware Update
25.1 Introduction
iChip accepts remote firmware updates from an HTTP or FTP server. The firmware
update is stored as an .imz file on the host server and downloaded by iChip acting as a
client. iChip replaces its existing firmware with the new one through a special application
that is part of the .imz file. This method is especially convenient when managing
firmware updates in a globally distributed install base of internet-enabled devices.
25.2 Updating Firmware from a Remote Server
This method involves placing the firmware update .imz file on an HTTP or FTP server.
iChip has the provisions to use its respective HTTP or FTP client to download the
firmware update file and perform the update process.
Before the actual remote firmware update command can be issued, the following
parameters must be set:
USRV Defines the protocol to be used (HTTP or FTP), and the name of the host
on which one or more .imz files are stored.
UUSR Defines FTP user name (FTP only).
UPWD Defines FTP user password (FTP only).
UEN This flag indicates whether iChip updates to a firmware version that is newer
than the currently installed one only, or to any firmware version it finds.
In addition, an appropriate .imz firmware update file must be placed on the remote server
at the location specified by the USRV parameter.
Once the above parameters are defined, the firmware update process can be initiated by
sending the following command to iChip:
AT+iRFU
iChip returns I/OK to acknowledge receipt of the command. As the update process may
take up to 4 minutes to complete, iChip issues an I/UPDATE message to notify the host
that it is in the process of updating its firmware. The host must allow for an extended
delay period until iChip completes the process. Once completed, iChip re-boots the new
firmware and issues an I/DONE message when in dialup mode, or an I/ONLINE in
LAN mode.
Several safeguards have been instated to ensure a successful firmware update. The
firmware update file is structured by Connect One in a specific format, which allows
iChip to authenticate its origin as a legal firmware image. iChip also verifies that the
firmware update is the correct version for its hardware environment. iChip rejects an
update file if it contains an image that is identical to the one already installed.
The remote firmware update procedure is detailed below:
1. iChip downloads the new firmware imz file.