Sample dmesg output whilst ipw3945d is running:

[  267.032000] ipw3945: Microcode SW error detected.  Restarting.
[  267.032000] ipw3945: Error Reply type 0x00000005 cmd DAEMON (0x10) seq 0x0406 ser 0x004A0000
[  267.032000] ipw3945: request scan called when driver not ready.
[  267.032000] ipw3945: Can't stop Rx DMA.
[  268.404000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  268.828000] ipw3945: Microcode SW error detected.  Restarting.
[  268.828000] ipw3945: Error Reply type 0x00000005 cmd DAEMON (0x10) seq 0x0406 ser 0x004A0000
[  268.828000] ipw3945: request scan called when driver not ready.
[  268.828000] ipw3945: Can't stop Rx DMA.
[  270.200000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  270.624000] ipw3945: Microcode SW error detected.  Restarting.
[  270.624000] ipw3945: Error Reply type 0x00000005 cmd DAEMON (0x10) seq 0x0406 ser 0x004A0000
[  270.624000] ipw3945: request scan called when driver not ready.
[  270.624000] ipw3945: Can't stop Rx DMA.
[  271.996000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  272.420000] ipw3945: Microcode SW error detected.  Restarting.
[  272.420000] ipw3945: Error Reply type 0x00000005 cmd ADD_STA (0x18) seq 0x0407 ser 0x004A0000
[  272.816000] ipw3945: Error sending cmd #07 to daemon: time out after 500ms.
[  272.816000] ipw3945: Can't stop Rx DMA.
[  274.184000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  274.608000] ipw3945: Microcode SW error detected.  Restarting.
[  274.608000] ipw3945: Error Reply type 0x00000005 cmd ADD_STA (0x18) seq 0x0407 ser 0x004A0000
[  275.076000] ipw3945: Error sending cmd #07 to daemon: time out after 500ms.
[  275.076000] ipw3945: Can't stop Rx DMA.
[  276.444000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  276.868000] ipw3945: Microcode SW error detected.  Restarting.
[  276.868000] ipw3945: Error Reply type 0x00000005 cmd ADD_STA (0x18) seq 0x0407 ser 0x004A0000
[  277.236000] ipw3945: Error sending cmd #07 to daemon: time out after 500ms.
[  277.236000] ipw3945: Can't stop Rx DMA.
[  278.608000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  279.032000] ipw3945: Microcode SW error detected.  Restarting.
[  279.032000] ipw3945: Error Reply type 0x00000005 cmd LEDS_CMD (0x48) seq 0x0409 ser 0x004A0000
[  279.032000] ipw3945: Can't stop Rx DMA.
[  280.404000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  280.828000] ipw3945: Microcode SW error detected.  Restarting.
[  280.828000] ipw3945: Error Reply type 0x00000005 cmd DAEMON (0x10) seq 0x0406 ser 0x004A0000
[  281.328000] ipw3945: Error sending LEDS_CMD: time out after 500ms.
[  281.328000] ipw3945: request scan called when driver not ready.
[  281.328000] ipw3945: Can't stop Rx DMA.
[  282.696000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  283.120000] ipw3945: Microcode SW error detected.  Restarting.
[  283.120000] ipw3945: Error Reply type 0x00000005 cmd LEDS_CMD (0x48) seq 0x0409 ser 0x004A0000
[  283.120000] ipw3945: Can't stop Rx DMA.
[  284.492000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  285.212000] ipw3945: Microcode SW error detected.  Restarting.
[  285.212000] ipw3945: Error Reply type 0x00000005 cmd TX (0x1C) seq 0x0000 ser 0x004A0000
[  285.212000] ipw3945: Can't stop Rx DMA.
[  286.584000] ipw3945: Detected geography ABG (13 802.11bg channels, 23 802.11a channels)
[  287.092000] ipw3945: Microcode SW error detected.  Restarting.
[  287.092000] ipw3945: Error Reply type 0x00000005 cmd TX (0x1C) seq 0x0000 ser 0x004A0000
[  287.092000] ipw3945: Can't stop Rx DMA.