WORKING ! Bluetooth Control of CPC telescope (and others)

[skybond]

Hi,

I have been trying to get my Celestron CPC scope working over Bluetooth for a couple of days now. I have finally cracked it and it is working very well. I thought I would share the process. This is a really great solution for me since it means I can control my CPC from inside the house and the range seems to be very good (going through a VERY solid wall with no problems at all).

First, the serial adaptor is Max Value Bluetooth to Serial / RS232 Adaptor: Amazon.co.uk: Electronics & Photo The Bluetooth to serial adaptor costs £22.

This unit plugs into the serial cable which then connects to your handset (in the case of the CPC). The unit comes with a male to male converter.

The first step is to program the serial controller. You can do this using Hyperterminal in windows or using Terminal on the MAC. The only parameter you need to change is the BAUD rate since this is initially set to 19200 and you need 9600. The command you need is ATL1. Once you have done this you can disconnect the serial adapter from your PC/MAC. Please note that the switch must be set towards the serial port in order to do this. Once you have removed it you must change the switch over to point towards the antenna.

Now you must link together the two middle pins on the bottom row of the serial connector (the row with 4 pins). I achieved this by getting some pliers and pulling out the two middle pins on the male to male converter. I then put in a little link on the bluetooth adapter. I made this link from a piece of wire tie since this is what I had handy. Once the two middle pins (on the row of 4) are connected I simply plugged this into the doctored end of the male to male converter (I removed the 2 pins so I got a snug fit).

Once you have done this you will hopefully find that everything works seamlessly. Note that the password for the bluetooth to serial converter is 1234.

Any questions then please let me know. I am very happy with the result.

Trevor

[dark knight]

That's really interesting, might try it for my eq5 synscan, would save having cables trailing to the mount, I presume the handset would need to be in pc direct mode. This will be extremely useful. In the box contents it mentions a power supply, can you clarify please,,thanks...

Carl

[barkis]

Why is it necessary to link those two pins?

Ron.

[skybond]

It certainly does help to reduce the number of cables. The unit needs a 5V supply and this is via a USB type interface which you can power from a PC (using your own cable) or from the supplied mains adapter. You might already have a 12V to USB cable lying around so you can power it from a cigarette socket.

Regards,

Trevor

[skybond]

Regarding linking the two pins ... Since the CPC only supplied Rx, Tx and ground there is no flow control used. The Bluetooth adapter does have an option to switch off flow control but I do rather suspect that this is only for software flow control (Xon/Xoff). You therefore need to fool it into thinking that hardware flow control is being used. This works by linking the two pins together. These are RTS and CTS (Ready to Send and Clear To Send). This means that the device is always Cleared to Send when the Ready to Send is set by the handset.

[yesyes]

Sounds useful.

Just to make sure, you use the adapter on the scope side and existing bluetooth on your PC?

Or does the adapter come with a sender and receiver? (doesn't look like that on the Amazon page)

[skybond]

You use the adaptor on the scope side and you need bluetooth on your PC or notebook.

[barkis]

Just been giving mine a test, operating from the desktop puter in a spare bedroom, to the Obs. 50 metres away, and through three walls with no probem. At least the communication works, I have yet to use the scope, but I need to have a wireless CCTV set up to see what's going on..

Ron.

[skybond]

Ah, for wireless CCTV I would use X10. Not strictly wireless but it would use the mains cabling that you no doubt have already going to your observatory.

[merlinxlm]

Do you happen to know if this system is compatible with the EQmod system?

Thank you.

[skybond]

Basically serial control is straightforward. There are no fast speeds used so the Bluetooth to serial adapter should be able to do exactly the same job as a serial cable. Normally the issue is Bluetooth transmission range and in my experience this adapter is very good.

If you can control your scope using the serial cable then it should work using the Bluetooth to serial adapter.