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CC2500 - Oh how I hate you!

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I have a few Anaren A2500R24A modules based on the TI CC2500 First of all I'll state that when I purchased I assumed these were similar to the CC2420 that I've used before, 802.15.4, but as I've learnt never assume anything and always triple check before purchasing, won't be making that mistake again...
I've been banging my head against this same wall for some time now and I'm stumped how to go forward.

I've got the SPI connection up and running, I'm able to talk to the device, read and write registers, read the status byte and the state machine.

Just in case I'm doing something stupid I'll explain how I go about this.
Power up, the device is reset, Rx & Tx registers are flushed, configuration registers are written, the state is checked and it is Idle.
I then put some data into the Tx buffer, I'm using variable length so I'll use something like
CC2500_Burst_Write(data, CC2500_REG_TXFIFO, length);
Where the data is say, 0x04, 0xDE, 0xAD, 0xBE, 0xEF, 4 being the length then the data itself
I then strobe STX, if I poll the state I can see it transition from Idle to Tx back to Idle
Is this confirmation that it has transmitted or should I be checking something else also?

On the Rx side of things I run into problems where I'll either get constant Rx overflow without Tx being on, or when I do try and Tx I get nothing.

I purchased a CC2511 RF sniffer usb dongle thinking this would help but it's even more of a pain than the CC2500, firstly the thing doesn't come programmed so it's worthless until you fork out for the programmer also, but then you can't just let it sit there and scan like I can with my 802.15.4 sniffer, you have to program it with the specific settings otherwise nothing, but even then I still can't get the thing to receive a dicky bird!

I've tried just copy pasting the settings from the Anaren files into the sniffer and also copy them but manually change the RF settings in case of clk differences.

I don't know where to go from here, I'm not entirely sure what I'm doing is correctly or how I can check this thing is actually transmitting or why the Rx is always overflowing. One thing I can say is I'm ready to get the hammer out on these things but unfortunately it's part of my project so I have to resist for now.

I'm going to give it a few more days then I think I'll pick up some of the Microchip MRF24J40MA modules. Is this only difference between MRF24J40MA and MRF24J40MB the output power/range?


--- Quote from: logictom on July 25, 2011, 08:51:33 am ---
I'm going to give it a few more days then I think I'll pick up some of the Microchip MRF24J40MA modules. Is this only difference between MRF24J40MA and MRF24J40MB the output power/range?

--- End quote ---

From my Motorola book ( master selection guide ) , it looks that this markings is about the class of operation as amplifiers,
Class A or Class B.  :)

i gave up on CC1101 last time. until the time comes again...

As I said on the shout box, I've worked with the CC1110 chipset which is fundamentally the same but lower frequency.

I've not used burst write (I was working with OOK transmissions, which are outside of the normal state machine control). That said, I did have the following problems:
1. Configuring the AGC on the RX side was frequency and transmission rate dependent in the extreme. It was very easy for it to get overwhelmed and generate garbage.
2. I was initially using a dev kit made by TI and if the two units were too close together (about 2-3m) then the link wouldn't work, even on a very low power.
3. I really struggled with the state machine getting stuck where I didn't expect it, but this was because I was essentially trying to avoid using it altogether.

Thanks for the feedback guys, I've been back and forth with the tech support that make these modules and I'm still having no luck... I'm going to cut my losses and move back to the CC2420 which will hopefully put my project back on track :)


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