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fmc30rf and the trf3720

How can I relate what I'm seeing in the data sheet for the trf3720 (IQ Modulator), that is,

N-Divider
Prescaler Div p/p+1
RF Divider
Sum Delta Control
Div 2/4/8
Vcm D/A

to the initialization code for the trf3720, that is,

LO_DIV
fVCO
PLL_DIV
NINT
NFRAC
PRSC
fN

I understand that some of these match up, but I'm looking for a methodology and an explicit, direct, mapping.

Is there any documentation on the methodology for the configuration of the trf3720, as shown in the fmc30rf_trf3720.cpp source file? I'm trying to understand the theory behind the derivation of the trf3720 configuration values. In other words, how do I take an LO_TX and know what to write to the trf3720 SPI registers.

This topic is being closed because the issue is considered as resolved by 4DSP. Feel free to create a new topic for any further inquiries.
No, I guess you can close this thread.
Dear Stuart,


I am following up with you, you haven't reported back to me, do you want me to get a sales engineer to contact you to discuss that further?


Best Regards,
Arnaud
Stuart,


No. There is a C++ function doing that given many parameters but we don't have methodology documentation. The function has comments almost on every line and what happens in there is very straightforward.


Someone wrote that function by looking at the integrated circuits literature from the manufacturer as well as the FMC30RF user manual.


Here also, I think you need more assistance than other customers who been perfectly able to integrate FMC30RF on their products, therefor we would need to arrange an engineering support contract. Shall I get a sales engineer to discuss that further with you?


Best Regards,
Arnaud


Best Regards,
Arnaud
Is there any documentation on the methodology for the configuration of the trf3720, as shown in the fmc30rf_trf3720.cpp source file?
Dear Sir,


There is a one to one mapping between the register numbers in the datasheet and the bar+n writes in fmc30rf_trf3720_init(). 'bar' is the stellarIP address of the first SPI register in the TRF3720.


fmc30rf_trf3720.cpp is programming 7 registers in the TRF3720 chip. When the software writes at bar+1, register 1 of the TRF3720 is hit.


The content of all the register is created in the same function. I haven't checked them all but when the comment says "//PWD_LO_DIV; Power down frequency divider in LO output chain 1 (1 = off)" I can search for "PWD_LO_DIV" in the datasheet and find some occurrences.


I hope that helps,
Arnaud