DeviceMaster Software Developer Kit RedBoot Command Overview

The DeviceMaster boards run a bootloader based on RedHat’s RedBoot program. In addition to the DeviceMaster compatible TCP and MAC mode network interfaces RedBoot provides a boot console interface that can be used to perform various functions:

RedBoot CommandsDescription
Autoload time-outSets the number of seconds after network initialization that the bootloader will wait before starting the default application program from flash ROM. A time-out value of 0 will disable auto-loading of the default application. The maximum value is 255 seconds.

timeout [{seconds}]

RedBoot> timeout
Timeout 9 seconds
RedBoot> timeout 5
Timeout 5 seconds
Board revision Sets or displays the board revision. Do not change the board revision of a DeviceMaster.
RedBoot> boardrev 
BoardRev 7
Cache The cache command is ignored in the DeviceMaster Bootloader, the Bootloader is always cache disabled.

cache [[ON | ] [off]]

Chassis type The chassis command displays the hardware chassis type (DeviceMaster PRO, DeviceMaster RTS or DeviceMaster UP)
Checksum The cksum command computes and displays the POSIX 32-bit CRC checksum of the specified region.
Disable Executing the disable command will prevent the Bootloader from loading the default application after the initial timeout period (which is set using the timeout command).


dump The dump command is used to display the contents of memory. The starting address of the region to be displayed is specified with the -b option (required). The length of the region to be displayed is specified with the -l option (defaults to 32-bytes).

dump [-b <location>] [-l <length>]

RedBoot> dump -b 0x10 -l 64
0x00000010: E59F F018 0000 0000  E59F F018 E59F F018   |................|
0x00000020: FFFF FFFF 007C 058C  007C 0610 007C 0648   |.....|...|...|.H|
0x00000030: 007C 06C4 FFFF FFFF  007C 07AC 007C 0794   |.|.......|...|..|   
Flash Image System (fis) RedBoot implements a rudimentary file system that allows program and data files to be stored in flash. The are various fis commands that can be used to manipulate this file system. Typing fis followed by a carriage-return will display a list of sub-commands:

fis [create [-b base_address] [-l addr] [-s] [-f] [-e] [-r]] [delete] free] [init] [list] [load [-b] [-c] name]

RedBoot> fis
 *** invalid ‘fis’ command: too few arguments 
fis create -b  -l [-s] [-f] [-e] [-r]
fis free                             
fis init [-f] 
fis list [-c] 
fis load [-b] [-c] name

See Using the RedBoot Bootloader and Downloading Programs for fis procedures.

Executing a program The go command is used to execute a program. If no starting address is provided as a parameter to the go command, the entry address of the last file loaded into RAM will be used.

It is possible to load a program or data file into RAM from three sources: serial port (the 4-pin diagnostic header or external Port 0), Ethernet (from a TFTP server or via TCP), or from flash ROM on the DeviceMaster board.

Help The help command displays a list of available commands and a short usage specification for each command.
History The history command displays the command history buffer.
HTTP authentication method Controls the type of authentication required for HTTP access.

auth { [noaccess] [none] [basic] [md5] [invalid] }

IP configuration Setting the IP address to disables IP networking. Setting the IP address to causes the bootloader to use BOOTP to request an IP address.

ip [{ip_addr] [ip_mask] [ip_gateway}] 

RedBoot>  ip
IP Config: IpAddr= IpMask= IpGate=
RedBoot>  ip
IP Config: IpAddr= IpMask= IpGate=

If only one parameter is provided to the IP command, the IP address value will be changed and the mask and gateway will be unaffected. Changes to IP configuration will take effect after reset.

Loading a fileThe load command loads files into the DeviceMaster.

load [{-r} ] [{-v} ] [{-h <host>}] [{-m {TFTP | xyzmodem}] [{-b <base_addr>} <file_name>]

It is possible to load a program or data file into RAM from three sources: serial port (the 4-pin diagnostic header or external Port 0), Ethernet (from a TFTP server or via TCP), or from flash ROM on the DeviceMaster board. Loading from flash ROM is described in fis load. Loading from serial port or Ethernet is done using the load command. Files loaded with the load command default to Motorola S-Record format (which must end with a single “Entry-Point�? record).

It is possible to load a binary file with the load command by using the -r and -b options.

Loopback test The loop command runs a loopback test using an external RS232/422 loopback plug or (if supported) using the internal loopback feature of a single port.
MAC address Sets or displays the MAC (Ethernet) address. Do not change the MAC address of a DeviceMaster.


RedBoot> mac
MAC: 00 C0 4E 0B FF FA
Memory compare The mcmp command compares two blocks of memory.
Memory copy The mcopy command copies a block of memory to a destination address.
Memory display The x command displays (examines) memory contents in hex.
Memory fill The mfill command fills a region of memory with a specified value.
Model number The model number is used by applications to determine what hardware features are available on the board. Do not change the model number of a DeviceMaster.


RedBoot> model
Model 5002120
Password Changes the DeviceMaster password used to authenticate telnet and HTTP access. Unlink other commands, the password command will not display the current value of the password. The password command always sets the value of the password. The password length is limited to 15 characters.

password [{password}] 

RedBoot> password
Password ’’
RedBoot>  password FooBar1 
Password ’FooBar1’
Ping The ping command sends ICMP ping requests to the specified address and displays the results.
Reset The reset command uses the watchdog timer hardware to perform a hardware reset of the DeviceMaster.


Secure config enable The secureconf command sets/shows the state of the secure configuration flag.

If enabled, configuration changes will only be allowed via a secure connection (https, ssl, ssh).

Secure data enable The securedata command sets/shows the secure data enable flag.

If enabled, serial port data will only be transferred via secure connection (ssl).

SNMP enable The snmp command enables/disables the SNMP agent in the standard SocketServer and NS-Link applications.
Telnet enable/disable Allows the user to enable or disable telnet access to the DeviceMaster.

telnet [[disable | enable]] 

Accepted values are enable and disable:

RedBoot>  telnet
Telnet enable
RedBoot>  telnet disable
Telnet disable
Telnet timeout The teltimeout command sets/shows the idle timeout setting for telnet connections.
Terse mode In order to provide a console interface more amenable to programmatic control, the bootloader may be put into terse mode.


The significant features of terse mode are:

  • No prompt is issued.

  • Command strings are not echoed

  • All responses consist of a single line. If the command was successful, the response string begins with “+ �?. If the command failed, the response string begins with “- �?.

Comtrol recommends that supervisory programs written to the interface with the DeviceMaster bootloader ignore lines that do not begin with “+ �? or “- �? in case bugs in some commands improperly display diagnostic information.

Test RS-485 Ports The t485 command runs a port-to-port test of two RS-485 ports.
Version The version command displays the bootloader version and build date:
 RedBoot> version
 Comtrol DeviceMaster Boot Version 1.11
 RedBoot(tm) debug environment - built 11:00:47, Feb 25 2002
 Platform: Comtrol DeviceMaster (ARM 7TDMI) 
 Portions Copyright (C) 2000, Red Hat, Inc.
 Portions Copyright (C) 2001, Comtrol Corp.

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