Implementation of Frequency Hopping using an external Trigger

Hi Oliver,

We will get back to you.

Regards

Rahul

Hi Rahul, 

Thank you.

To offer a better explanation:

According to a work colleague, the requirement is to use 1 channel and both LOs, Whilst 1 on 1 frequency we want the other LO to begin tuning to the next frequency we want to index each tuning frequency using GPIO and then a "trigger" pin to make the hop on the next LO repeating this sequence over and over.

What would the test set up look like for this too?

Thanks again

Hi Oliver,

There are two way you can trigger the  HOP signal one is using the SPI command and other is toggling the GPIO pin. In our setup FPGA does the toggling of the GPIO pins. In order to activate for hoping via GPIO can be done by choosing Table Index Control as GPIO

In order to make used of both the LO, please select MUX mode option as shown below. In the MUX mode two PLLs are used. This mode allows one PLL to tune when other PLL is in use and in this way transition time within each HOP frame is reduced.

In order to select the table and selecting the index within the table can be done by providing entries O/1 for selecting table A/B and providing sequence of index for Table Index Sequence respectively

The respective GPIO pin for Table Index and Table Selected can be assigned as shown below

For more details please go through the Frequency Hopping chapter in user guide.

Regards,

Rahul 

Single channel Auto FFH Test.zip

Thank you,

Can you advice on what the Hardware test setup would look like to control the GPIO?

I am using Argo Navis version 0.24.01. Is it worth while to install a newer version?

I have attached my Taxidi file.

i have one GPIO header pin connected to waveform Generator, i can now see that triggering a hop between 2 frequencies. Below is my executed sequence, i can hop between the first 2, 00 and 01 using DGPIO 1. No how can i add a third pin to continue through the table?

Hi Oliver,

Glad that your are able to hopping between the frequencies using GPIO. The reason why you were able to hop between first two frequencies is because you have used one GPIO pins which will have two outcome 0 and 1. In order to move further in the hop table, you need to connect multiple GPIO pin header (in your case for generating 00,01,10 and 11 you need two GPIO pins). In order to change the GPIO pins you can do that using the ''Control Hopping by GPIO'' . 

Here you can change the HOP table index sequence and based on the number provided in the hop table index sequence the number of GPIO pins will be enable.

For example, the number for 'hop-table-index-sequence-8-entries' is from 0 to 3, hence two GPIO pins are enabled as shown below

One has to note that Table Select Pin is for changing the HOP table. Another example where I have changed the 'hop-table-index-sequence-8-entries' which contain number from 0-9, hence you can see that additional pins have been enabled 

Regards,

Rahul 

thank you again, 

What would the Physical test set up look like? 

Currently I have one GPIO being controlled by a waveform generator outputting a 1hz square wave.

what methods would you recommend to control 2 or more GPIOs? 

I have an oscilloscope which can output a binary pattern that I have considered using. Another option I have looked it is using an Arduino.

What would you use to to control each index pin?

 Above is the hop table, What's the difference between hop index and code?

What i intend to do is: 

• Using a single channel with both LOs on Tx1
• GPIO Pins to index a row of the hop table
  • Next LO begins tuning next frequency 
• A hop pin to trigger the change between LO1 and LO2 and vice versa.
• 

Once this is working I intend to use one hop table with 16 frequencies with this method. 

Thanks Again for your help on this