Raspberry Pi Differences

The Problem that instigated this investigation was that I bought two Aqprox Wireless-N Nano USB Wireless adapters and could not get one to work on my test-rig Raspberry Pi. After doing all the usual swapping around, the conclusion was that there were differences in the R-Pi's that the adapter would not work on one, but was quite happy on the other.

As found from: http://www.raspberrypi-spy.co.uk/2012/09/checking-your-raspberry-pi-board-version/



pi@raspberrypi:~ $ cat /proc/cpuinfo               *** Model B  Revision 2
processor       : 0
model name      : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS        : 2.00
Features        : half thumb fastmult vfp edsp java tls
CPU implementer : 0x41
CPU architecture: 7
CPU variant     : 0x0
CPU part        : 0xb76
CPU revision    : 7

Hardware        : BCM2708
Revision        : 000f
Serial          : 000000002dab1189
pi@raspberrypi:~ $

works with Ralink Ok

Last login: Mon Jan 16 09:17:15 2017               *** Model B revision 1
pi@raspberrypi:~ $ cat /proc/cpuinfo
processor       : 0
model name      : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS        : 697.95
Features        : half thumb fastmult vfp edsp java tls
CPU implementer : 0x41
CPU architecture: 7
CPU variant     : 0x0
CPU part        : 0xb76
CPU revision    : 7

Hardware        : BCM2708
Revision        : 0002
Serial          : 000000004cb2f7c8
pi@raspberrypi:~ $

Fails with Ralink  ??? why?


http://elinux.org/RPi_HardwareHistory

www.element14.com/community/docs/DOC-78141/l/identifying-your-model-of-raspberry-pi
- Sorry, that's member only access.

http://www.raspberrypi-spy.co.uk/2012/09/raspberry-pi-board-revisions/

and for completeness:
en.wikipedia.org/wiki/Raspberry_Pi


From the elinux web site I ascertained that the unit that didn't work was a Model B Revision 1. It does not have any mounting holes. The one that does work is a Model B revision 2.  So I will label the procinfo outputs above.

Further research needed to determine why it doesn't work, but meanwhile I'll have to use the Zyxel wireless dongle

2017-01-18 Response from R-Pi forum:

The RPi B rev 1 has polyfuses in the power circuits of each USB port. The fuses limit the power too much for WIFI and so only low current devices such as keyboard and mouse will work. The fuses were removed in rev2 and power is directly connected to the 5V supply.
On my rev1 boards I removed the fuses and soldered wires across the pads to make them more like the Rev2 board.

So now we know.