Unreliable Startup of Sine Wave Generator Using MPC5744P

cancel
Showing results for 
Search instead for 
Did you mean: 

Unreliable Startup of Sine Wave Generator Using MPC5744P

89 Views
zcampbell
Contributor I

I have one issue that I cannot see why is a problem: I am seeing only in hardware signals that anywhere from 15%-50% of the time, on startup of the MCU, the sine wave in the attached model is not being started.  I have to manually restart (turn off and turn on, sometimes many times) the MCU to get it to start up - and I have to probe the signal to determine if it's starting.  Whatever method that's being used in the attached model to start up the sine wave, maybe there's another, more reliable, method??

 

I have one general question for the community:  When using the blocks within the MBDT for the 5744P called 'CTU Get Conversion Result'.  If you have more than one ADC sample you are trying to retrieve from the ADC, how do you know which sample will come out of each block when using these blocks?  The attached model uses synchronous ADC sampling on both ADC0/ADC1 and I would like to understand using these blocks how I can anticipate which block will house which ADC sample.  Is there a way to determine? 

CTU_Get_Conversion_Result_Capture.PNG

0 Kudos
2 Replies

41 Views
zcampbell
Contributor I

Hello @mariuslucianand 

 

Have you had a chance to look into the unreliable startup of the sine wave generator.  I still do not understand how it could be that it only starts up sometimes.

 

Thank you,

Zak

0 Kudos

63 Views
mariuslucianand
NXP Employee
NXP Employee

Hello @zcampbell 

For the first question, I have to investigate the mentioned behavior.

For the second question, the results are stacked in a queue. For each result you want to get from the queue, you have to use the CTU Get Conversion Result block. Now, in order to know which ADC provided the converted value, You have to consider the outputs: the first one gives you the ADC instance, the second gives the channel number while the last one provides the value.

For example if the ADCport = 0 and ch_number = 5 then the converted result comes from the ADC0, Channel 5. 

mariuslucianand_0-1614593628074.png

I will try to reply with a solution for the firs question as well, if I will be able to reproduce it.

Hope this helps, Marius

 

 

0 Kudos