AFE7950EVM: Configure 7950EVM by LabVIEW

Chaoyang Tsai

Prodigy 135 points

Part Number: AFE7950EVM
Other Parts Discussed in Thread: AFE7950, LMK04828,

I want to configure the 7950EVM by LabVIEW. I have the FTDI lib and Afe79xxPg1.txt.

The 7950 has 3 spi buses(SPI/SPIB/SPIB2).

1.Which bus is used by the Afe79xxPg1.txt? How to distinguish?

There is no lmk ctrl in Afe79xxPg1.txt.

2.How to get the setting of lmk?

over 3 years ago

0 David Chaparro over 3 years ago

TI__Mastermind 18831 points

Hi Chaoyang,

The AFE7950 has three SPI interfaces with one being the main SPI interfaces, SPIA or SPI. When programming the AFE using Latte we are only using SPIA, so you can also use SPIA for programming. On reset the AFE only has SPIA enabled and the two auxiliary ports, SPIB1 and SPB2, have to be enabled through SPIA.

To enable the logging of the LMK writes you can add the 'lmk.logEn ' parameter to your script, before the bringup function, and set it to 'True'.

Regards,

David Chaparro

0 Chaoyang Tsai over 3 years ago in reply to David Chaparro

Prodigy 135 points

Hi David,

I update the script as following pic.But I didn't get the lmk log.

Where is the lmk log? Or What did I miss?

0 David Chaparro over 3 years ago in reply to Chaoyang Tsai

TI__Mastermind 18831 points

Hi Chaoyang,

I believe the issue might be the devInit script. Please add 'lmk.logClassInst=logDumpInst' to the devInit script and then the LMK writes will be logged in the same file as the AFE writes.

Regards,

David Chaparro

0 Chaoyang Tsai over 3 years ago in reply to David Chaparro

Prodigy 135 points

Hi David,

I add the cmd but still didn't get the lmk log.

There are some lmk.logEn=False in the devInit.py. I change the value to True.

Is there anything missing?

0 David Chaparro over 3 years ago in reply to Chaoyang Tsai

TI__Mastermind 18831 points

Hi Chaoyang,

It looks like there is an issue with the lmk.logEn parameter. In the Latte script that you use to program the AFE change the lmk.logEn parameter to lmk.rawWriteLogEn = 1.

Regards,

David Chaparro

0 Chaoyang Tsai over 3 years ago in reply to David Chaparro

Prodigy 135 points

Hi David

There are two regions of LMK spi write, right?

0 David Chaparro over 3 years ago in reply to Chaoyang Tsai

TI__Mastermind 18831 points

Hi Chaoyang,

That is correct. All LMK writes are shown in the log file with the header 'LMK04828'.

Regards,

David Chaparro

0 Chaoyang Tsai over 3 years ago in reply to David Chaparro

Prodigy 135 points

Hi David,

SPIWrite 010f,14,0,7 dclkout3 is enabled

SPIWrite 010f,04,0,7 powerdown the dclkout3

So the afe7950 don't use the SYSREF signal ?

And some other clk also powerdown. These clks are not used by AFE7950?

0 David Chaparro over 3 years ago in reply to Chaoyang Tsai

TI__Mastermind 18831 points

Hi Chaoyang,

Not all clock outputs of the LMK are used. Please see the AFE7950EVM schematic to see how each output is being used.

The AFE does use SYSREF during bringup. The procedure that is followed is to turn on SYSREF before programming the AFE and once the required SYSREF pulses have been provided it can then be turned off.

Regards,

David Chaparro

RF & microwave

RF & microwave forum

AFE7950EVM: Configure 7950EVM by LabVIEW