Serin Serout possible wiring distance

[tasmod]

Ioannis and all,

Please forget these modules. The rudeness I received on the Ciseco forum from the manufacturers means I'm abandoning them.

[Ioannis]

Without a Datasheet is difficult to make something good.

There are many modules that can do the job. Do you have a target price and freq range?

Ioannis

[tasmod]

Hi Ioannis,

Unfortunately I'm stuck with these modules as the 'client' bought them.

I have his base requirements working 100% but I let myself in for more work when I mentioned signal strength output.

Trouble is the modules do not have any visual indication as to what they are doing. I'm working blind, other than turning leds on/off on my board at strategic points in the software.

I get confirmation after each AT command that the slave is in test mode.

It will not respond to anything else when in test mode other than "+++" guard characters for command mode, so I put in a time loop to turn test mode off later by software.

The master sits and waits after confirming it is in test mode. Then nothing. Both should be transmitting at 1 second intervals with RSSI information in db fed on the serial port from the master. They loopback the RSSI.

I do not have an interface to connect to my PC to test, besides that is no use anyway as the modules will be standalone. Testing on a PC just proves they work that way.

I also considered another set of rf modules originally from another manufacturer. They had red and green status leds on board. Red when TX, green when RX. Both on for config mode. Much more useful.

I chose the Ciseco modules because of power output and the support forum.

At first on the forum I thought they were a bit defensive and odd. Now they insult my admittedly limited intelligence and are downright rude.
I don't believe they read the replies carefully. I had to repeat what I had tested, even though the answer to what I had done was two posts up.

I've spent tens of hours on this. I'm leaving them just doing the basic function the 'client' wanted. On/off red/green light.

'Client' is a misnomer, I'm doing them for free.

Rob

[tasmod]

THIS IS FROM THEIR SETUP RSSI INFO PAGE

The AT commands are in the brakets at the side. Compare to my code.


In order to test the range between two devices, it is possible to put two XRF's into a special mode via either the AT commands or the XCM. Once in the special mode it will send a packet once a second from an XRF connected to your PC (master) to another 'remote' (slave) XRF. The slave XRF will measure the incoming RSSI level and send the packet straight back. The master XRF then measures the RSSI of this and displays both packets serially.

The image below shows the continuous output you will see on your screen. We're interested in the first two values:
aSSRSSIS-045 (the signal strength of 045) received at the slave and
aMMRSSIM (046) received at the master (your PC).


HOW TO SETUP
During setup we advise turning off any other XRFs, so that only the two you are using to test range are turned on. If this is impossible then change the two devices to be tested to another PANID.
First set up the slave (remote end).
1. Configure on your PC using XCM or AT commands
2. Change ATNT (node type) to 4 (ATNT4)
3. Write to permanent memory (ATWR)
4. Close the session (ATDN)
Unplug the first XRF and plug in the second XRF
Configure the master (PC end)
1. Configure on your PC using XCM or AT commands
2. Change ATNT (node type) to 3 (ATNT3)
3. Write to permanent memory (ATWR)
4. Close the session (ATDN)
5. Leave the second XRF on your PC and in a serial monitor window as above
Test Power up the first XRF with 2 to 3.6v, at a distance over 1 meter away. Two AA batteries are perfect for this, but make sure your voltage is not greater than 3.6v
You will see the two RSSI levels being written to the screen once a second.
MAXIMUM RANGE When the RSSI figures reach 88 to 92 you've reached the maximum distance you can achieve reliably. If you are planning to run at distances close to this then we advise conducting the test a few times during the day to make sure you are getting a reliable connection.

[Ioannis]

Well, it seems OK to me. With direct connection to PC did you have any better luck?

I understand it is very annoying.

How are you checking if the transmitter is really transmiting?

Ioannis

[tasmod]

PC connection, that's one of the problems, I don't have an ftdi interface or want to buy theirs at £25 as it's at my cost.

I tried direct 9pin max232 connection but I don't get a response except echo back.

I'm also completely puzzled as to why I can't hear anything except a low dull pulse on my UHF sdr receiver when in test mode. It's supposed to be a higher power version rf module. I should see and hear the pulses at 868.3 mhz.

Yet I can pick up my signal generator strongly which is 100 times less output!

Every now and then I get a good visual signal with high strength but it's not consistent.

I will have to abandon the RSSI output and just go to the base use for the modules. It needs to be boxed and out by early next week.

Rob

[tasmod]

OK don't know why I didn't think of it before, I used my scope on the TX RX pins when both units are in test mode.

They have data back and forth at 1 second intervals. That means they are transmitting and receiving.

So, it's down to this routine not working. Given the details above I just can't see why :-

sigstrength:

    IF jump = 1 THEN rssioff     ; check input to reset to serial                                             
    DEBUGIN  3000,sigstrength,[WAIT("aSSRSSIS-",sigfield)]    ; get slave signal strength value                                        
    DEBUGIN  3000,sigstrength,[WAIT("aMMRSSIM-",sigcontrol)]  ; get control signal strength value 
    
    LCDOUT  $FE,$80," Light Unit ",sigfield                                       
    LCDOUT  $FE,$C0," Control Unit ",sigcontrol                                         
    GOTO sigstrength