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Posted 2007/02/22

Setting up a Stargate spb400 for use as a mote gateway

For our green house monitoring application we need a gateway to receive data from wireless motes in the greenhouses and enter the data into a database. We are using a Stargate processor board in a window of the Lyle building which has line of sight to the greenhouses. This post describes what was needed to get the Stargate running.

We have the port replicating daughter card for the processor board which provides Ethernet, serial, power and host-USB. The processor board itself has a 400Mhz RISC CPU with 64MB or RAM and 32MB flash storage. We bought a regulated AC power supply to give the board the 6V 1A it needed for power. The board will eventually be wired into the University LAN and use a Java program to communicate to the sensors in the greenhouses via a mote which will be plugged directly into the Stargate board.

The Stargate comes with Linux 2.4 pre installed. We use a serial link to another Linux box to see the boot process and to log into the board. The minicom settings are:


x A - Serial Device: /dev/ttyS0
x B - Lockfile Location: /var/lock
x C - Callin Program:
x D - Callout Program:
x E - Bps/Par/Bits: 115200 8N1
x F - Hardware Flow Control : No
x G - Software Flow Control : No

Start minicom and then power the Stargate. You will see the bootloader followed by the Linux kernel booting, then you will end up at the prompt.


FLASH_BASE=00000000
PXA: Evacuating 1MB of Flash to DRAM at: A3E00000
done
Map Flash virtual section to DRAM at: A3E00000
setting flashword=50000000
Flash style = 2x16
verify flash size...
btflash_init: mfrid=00890089
...
...
...
Booting Linux image
Uncompressing Linux................................................... done, booting.
Linux version 2.4.19-rmk7-pxa2-star (eepp@clyde) (gcc version 3.3.2) #1 Fri Aug 13 14 STARGATE Version 7.2
CPU: XScale-PXA255 revision 6
Machine: Intel STARGATE Development Platform
Ignoring unrecognised tag 0x00000000
Memory clock: 99.53MHz (*27)
...
...
...
derek login: root
Password:
Linux stargate 2.4.19-rmk7-pxa2-star #1 Fri Aug 13 12:58:00 PDT 2004 armv5tel unknown
login[156]: root login on `tts/0'

derek:/root# df -h
Filesystem Size Used Avail Use% Mounted on
rootfs 31M 13M 18M 40% /
/dev/root 31M 13M 18M 40% /
derek:/root# uname -a
Linux derek 2.4.19-rmk7-pxa2-star #1 Fri Aug 13 12:58:00 PDT 2004 armv5tel unknown
derek:/root#

This embedded platform is much better suited to our needs and because it runs Linux we don’t need to learn a whole bunch of new stuff to use it.