Lantronix MatchPort b/g Pro, Руководство по интеграции

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2: Description and Specifications
MatchPort b/g Pro Integration Guide 16
BOOTP_EN#
The BOOTP_EN# pin performs two functions simultaneously. It drives an optional
external diagnostics LED to indicate the status of the bootloader. It also serves as input
to enable booting from the network when no valid FW image is found in FLASH.
BOOTP enable
Holding BOOTP_EN# low (via switch or jumper) during and up to 10 seconds after a
reset allows booting the device with a FW image on a TFTP server only in case no valid
image is present on FLASH.
The MatchPort b/g Pro will issue a BOOTP request to acquire an IP address for itself, the
IP address of a TFTP server, and the filename of the FW image on the TFTP server.
Then it will fetch that file via TFTP, verify, and execute it.
Diagnostics LED
After supplying power to the unit or pressing and releasing the reset button, the
diagnostics LED turns on and stays on while the bootloader is running and does not
encounter any errors. After the bootloader loads firmware from serial, network or FLASH,
it turns off the LED right before handing over execution.
In case an error occurs during the bootloader operation, it will flash the LED. The pattern
will be pause, X * long flashes, Y * short flashes, pause, X long flashes, etc.
X is the first digit of the error number and Y the second.
Following are the currently implemented errors:
INVALID_BOOTLOADER_CHECKSUM 11
NO_FLASH_IMAGE_FOUND 12
BAD_FLASH_IMAGE_FOUND 13
BAD_COMMAND_PARAMETER 14
NO_BOOTP_RESPONSE 15
BAD_BOOTP_RESPONSE 16
NO_BOOTP_TFTP_IMAGE 17
RECEPTION_TIMEOUT 18
RECEPTION_OVERRUN 19
IMAGE_OVERSIZE 21
BAD_IMAGE_CHECKSUM 22
BAD_IMAGE_DESTINATION 23
INTERNAL_CODING_PROBLEM 24
Pin Connection Options
The circuit below is an example on how to correctly connect a switch (or permanent
jumper) and an LED to the BOOTP_EN# pin. The customer has the option of
implementing either the switch/resistor or the driver/LED or both or none.
The switch can be replaced by a jumper or hardwire. Having the hardwire in place means
that if the firmware image in FLASH becomes corrupt, the MatchPort b/g Pro will
automatically send out BOOTP requests over the network. This could be a security risk.
The switch or jumper allows BOOTP requests to be sent only after manual intervention.
If no switch/jumper/hardwire is installed, network recovery is only possible by issuing
a
!NL
command over the serial port.