Rockwell RCV144ACx, Справочник по командам

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AT Command Reference Manual
1048 3-29
3.2.7 AT** Command
** - Download to Flash Memory
The linear flash memory downloader in the modem firmware allows flash memory connected to the modem external memory
bus to be upgraded with revised modem firmware. This process transfers (uploads) the upgraded modem firmware (data)
from the host computer to the modem which transfers (downloads) the data to the flash memory device. Note that this
downloader function must be provided in modem MCU firmware initially installed in external flash memory, i.e., the
downloader does not support the programming of blank flash memory.
Programming the flash memory device is a two-step process.
1. When the AT** command is issued, the modem firmware boot loader is invoked and the user will first load a flash load
module (FLM) into the modem's RAM. The FLM contains the programming algorithm for the flash memory device being
programmed and any messages that may be sent during the load process.
2. The user will then load the new modem firmware which the FLM will then program into the flash memory device.
Procedure:
1. Install in the modem a flash memory programmed with the modem firmware; ensure that the flash memory device is
programmed with the sector secure mode set to UNSECURE (AMD only), otherwise the device cannot be re-
programmed in the modem.
2. Put the FLM file and the new modem firmware file (e.g., V1400DS.S37) in an appropriate directory on the computer's
hard disk.
3. Configure the communications application program for a DTE rate of between 9600 bps and 57600 bps (57600 bps is
faster) and RTS/CTS flow control. A load at 57600 bps will take approximately 2 minutes; a load at 19200 bps will take
approximately 6 minutes.
4. Check the modem for response by typing AT.
5. Initiate the download process using the AT**n command, where:
AT** or AT**0 Download speed is the last sensed speed (recommended command).
AT**1 Download speed is 38.4k bps.
AT**2 Download speed is 57.6k bps.
The "Download Initiated" message appears upon issuing the AT**n command.
6. Perform an ASCII upload of the FLM file (e.g., AMDE.S37) from the host computer to the modem RAM using an
industry standard communications software or an equivalent process (ensure that all ASCII translation or pacing is
turned off).
To abort the load at this point, wait for the FLM download process to time-out, send a bad S37 record, or reset (POR)
the modem. If the load process times-out, the modem must be reset (ATZ) before the FLM can be loaded again.
7. After the FLM has been loaded, perform an ASCII upload of the new modem firmware hex file (e.g., RC288ACi.S37)
from the host computer to the modem RAM using an industry standard communications software or an equivalent
process. There will be a 3-second pause after the first record of the RC288AXX.S37 file is sent, which is the FLASH
erase cycle. There is no turning back at this point.
If the flash download fails (because of a bad .S37 record for example) or the upload is aborted, as long as the modem
is not turned off or reset, it will remain in the flash load cycle and the upload can be re-attempted at step 7.
A "Wrong Device" message is displayed if an incorrect FLM is used. In this case, restart at step 5 and upload the
correct FLM file.
A "Wrong Hex file or flow control" message is displayed if an incompatible hex file format is used (non-Motorola S3
format) or if the DTE ignores flow control (the flash download uses both Xon/Xoff and RTS/CTS flow control). If the
wrong format was used, reinitiate the upoad at step 7 using a correct firmware hex file.
8. A "Device successfully programmed" message is displayed by the FLM at the completion of a successful download and
the modem will do a cold start.