Quote:
Originally Posted by Shano592
Well, I tried most of Saturday evening, and I could not get the Bluetooth module to work.
It definitely synchronises with the tablet, but it either isn't getting the signal to the LX200, or it isn't sending the response back from the LX200.
Either way, SkySafari just puts up the same error message, saying that, while it can establish a connection with the scope, it isn't getting anything back (it also says this without the scope being connected, only the BT module).
Without any real options to tweak things on the module, or the software, it looks like it is a dead end. Pity, it would have been a nice, cheap solution.
I guess I will have to look forward, and check out SkyFi. My tab has root, so adhoc wifi is doable.
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Hi Shane,
The first thing you should try is a simply loop back test.
Disconnect the cable to the telescope.
Make sure the switch on the module is set to SLAVE mode.
Using some test clips, short together pins 2 and 3 on the 9-way male serial
connector on the module. See here for which is 2 and 3.
http://www.db9-pinout.com/
Be careful not to short them to the metal shell which will be referenced to ground.
This will then have shorted TXD to RXD. Anything you transmit will be received
straight back.
Grab a Bluetooth Terminal Emulator app. Here is one -
https://play.google.com/store/apps/d...blueterm&hl=en
There are plenty of others.
Attempt to connect to the module. Anything you type on the terminal
should be echoed back because you have shorted the TXD and RXD pins.
You may need to configure the module. A module such as this uses an "AT"
command set. See manual here -
http://www.electronctl.net/Note/BLK-...20COMMANDS.pdf
The manual does not specify whether it will only respond to AT commands via the
Bluetooth interface, its wired RS-232 interface or both, but you could give the
Bluetooth interface a try.
Otherwise you will need to crate a "cross-over" cable, connect it to a PC and
use a terminal emulator like Hyperterminal to configure it.
The manual might suggest that the AT commands expect to be terminated
with a carriage return character and a line feed character.
Just try typing AT followed by the enter key to see if it responds with OK.
If not, try typing AT following by Control-m Control-j which is equivalent to
carriage return linefeed. If that still does not get a response, it might be that
the terminal emulator is intercepting and interpreting control-j and control-m
as just two control characters. Check if the terminal emulator has a configuration
where you can specify the line termination for sending and for receiving.
Historically, the LX200 communicated at 9600 Baud at default.
You should check the Meade manual for your model to determine the expected
Baud rate.
Using the AT command set, you can program an appropriate Baud rate
and check other settings.
At its heart, Bluetooth has a layer called RFCOMM that was purposely designed
to emulate RS-232 serial communication. So you possibly have a simple problem
such that one or more parameters of the module parameters needs configuration first.
There are plenty of modules on the market, including the Roving Networks RN-270M
for Bluetooth or the RN-240 or RM-270 for WiFi. These can be purchased online from
companies such as Mouser.
http://au.mouser.com/ProductDetail/R...Iz2Sf9GxneA%3D