Raspberry pi wifi for skysafari app

[Fizics (John)]

I have set up a raspberry pi as as a wifi interface for skysafari. Works out much cheaper than other devices but requires some basic unix knowledge.
The pi provides both the wifi for the iPad and serial connections for my nexstar.

[acropolite (Phil)]

Are you going to tell us how or are you just teasing....

[Steffen]

Since my SkyFi has recently died I would certainly be interested in a cheap alternative, especially if it involves Unix

Cheers
Steffen.

[Fizics (John)]

It's a great project if Unix doesn't scare you off. I will refer you to two articles and make some comments.

Follow the steps in this article first --- http://astroland.funxiun.com/remote-...and-skysafari/

At this point you can connect the iPad and raspberry pi to a wifi network which is ok if your at home. So setup the pi as a wifi hotspot by following the steps in the next article. I connect the pi to the 5v usb output on my scope battery pack.

http://elinux.org/RPI-Wireless-Hotspot (in step 3 I left out driver=nl80211)

My pi is a model B, the wifi dongle is element14's wi-pi which does not use the nl80211 driver.
The usb to rs232 cable referred to in the first article I use a chipi-x10.
I made a db9 to rj11 cable for my nexstar.

Give it a try I had absolutely no problems worked first go, different components than mine might cause you some grief. Cost me about $100.

[snowyskiesau]

I just tried this with 3 different wifi dongles and no success!
2 of the dongles were eBay cheapies and the 3rd was from AusPi.

It's not that I need a wi-fi access point, it just seemed like a cool thing to do with a spare Pi.

No idea what chipsets these wifi dongles use, I'll check that next.

[Fizics (John)]

Wifi adaptor must support Access Point. I bought the wi-pi from element14 confident they sold suitable devices. It uses an ralink chipset.
This might help you http://elinux.org/RPi_USB_Wi-Fi_Adaptersc
Good luck.

[snowyskiesau]

A bit more fiddling with yet another cheap wifi dongle and it now works. I get an error starting it via /etc/init.d but if I start the daemon manually, it starts up so I'm guessing a return code from the daemon is seen as an error.

According to lsusb, dongle is an RaLink RT5370.

It would been a bit of work on the iptables settings to be a useful general purpose AP but quite neat.

Back to the Pi camera!


EDIT: Problem was a type in the /etc/default/hostapd file. Tried again and both cheap dongles work. The other is an RTL8191.