TI CDCE Eval Board Writer. CDCE925 / CDCE937

This all started when i bought an eval board to test a component out. This eval board didn't work natively and i still wanted to use the part. This is the journey i took to get there.

I needed to make 3 clock frequencies and used this clock generator to try and do that. the part i really want to use is the CDCE937 which has 3 PLLs and 7 outputs. i got the dev board for the CDCEL925 because it was available.

The driver does not work and i couldn't get it to. so i resolved to program the device with an arduino thinking it couldn't be that hard....

A PC

An arduino or a microprocessor with I2C outputs

The Arduino IDE - https://docs.arduino.cc/software/ide/

TI clock pro - https://www.ti.com/tool/CLOCKPRO

Breadboard

A level converting circuit (probably not needed, but include anyways)

A TI CDCE dev board, or board with the chip on.

Spectrum analyser or frequency counter (for checking the output) oscilloscope might work in a pinch.

logic analyser - not required but handy

python script to convert clock pro output to something that can be used in arduino

arduino code

This step might not be required but it is good practice to not put different logic levels into each other.

this step is added to point out where the connections should go. some of the GND pins are grounded through a resistor and these should be avoided. the GND pin shown is direct to GND.

if you install clock pro and open the SW you will get the config wizard. put in your fin frequency and the number of outputs. then set the output frequencies then click generate setup.

It will get you to select a relevant device. for me this is the CDCE925. click view setup.

The setup will be made for you. i changed a few things. the dev board doesn't have Y5 connector populated so i moved this to y4

the input type was changed to LVCMOS.

when you have the setup you want ready. save the config as an intel hex file. we will convert this to something we can use in the next step.

in the end, we want to get the config from the last step into an Arduino program. to do this i made a python script that converts the hex file into a text file in the format i used in arduino.

i created a drag and drop interface to keep things simple. just drag the saved config into the window and the txt converted file will be sent to downloads.

you will need to install python on your PC. get this from the python website

to run the script simply navigate to it in command prompt with a cd "file path" then type "intel HEX to CDCE.py" and the GUI window will appear.

you may need to do a "pip install tkinterdnd2" first. i am not sure how to test if this is in the basic of python package.

drag and drop in the hex file you created and the txt file will be saved in downloads. it should look something like this

Open the arduino program and replace the highlighted section with the text from the file created in the last step. once this has been done you can upload the program to the device. in the serial monitor you will see some help text. if you type 1 and hit enter it should load config 1 to the device. and it should be outputting the frequency you want.

There is alot of debug and development code left in the program that may be useful. you could create more configs and load them in if you wanted to try out different configs and change them on the fly.