USB communication failure on filter parameter-change

Question

Hi! 
 
 I have a strange problem with my ADAU1462 based custom HW: 
 The situation is: 
 I'm well connected to the HW through USBi (SPI), .dspproj is "link compile download" and the connection status is "Active: Downloaded. DSP processing is ongoing and i can listen to the processed audio. 
 But when i now try to change the parameters of specific filter types (e.q bypass on<->off), the connection fails. 
 So far, i tested the following and found these to cause the issue : 
 - Filters->Second Order->Single/Double Precision-> Clickless HW slew->All three filter types 
 - Single/Double Precision-> Clickless SW slew->All types tested except ext. triggered types 
 
 No issue happens when using the following: 
 - Filters->Second Order->Single/Double Precision-> No slew ->All four filter types 
 
 Beside of filters, i'm using several other DSP processing blocks like gains (with and without SW slew), mute, polarity, switches, dynamic processors (limiter/compressor), delay. All of these cause no problems. 
 
 Does anybody have an idea how to resolve this issue, or how to further debug it? 
 
 BR 
 Matthias

Harishgowtham · Accepted Answer

Hello Matthias, 
 I guess that this is an issue with the DLL of ADAU1462. This problem comes when it writes to the safe load addresses in DM1 (the Coeff of the filters with slew) in run time. The SS calculates the new Coeff for the slew- filters when you change the GUI controls, but I guess it fails to write to the DSP. However, when you do link compile download again with the new filter parameters then the filter works as it should. So, I don't think this is a communication problem between the USBi and the DSP. 
 The ADAU1466 or ADAU1467 DLLs do not have this issue. So, Change the processor on the hardware config to the ADAU1466 and it should work fine. The only detail is that you will have to watch the memory usage in the Output Report to be certain you are not exceeding the memory in the part. The compiled code will be the same. 
 Just try picking any of these processors (ADAU1466/67) and run the same code. Then control the slew filters in run time if it changes the output then we can conclude that the issue is with the ADAU1462 DLL. I have also verified that here. So, keep me posted. 
 Steps to switch the program from ADAU1462 to ADAU1466. 
 Please save another copy of this project somewhere. 
 1) In the config window, drop in the new processor and attach it to the USBi GUI. It will probably enumerate as IC2. 
 2) Go to the schematic page and select all. 
 3) Right click anywhere on the schematic window and select "Change IC" and change it to IC2. 
 4) You will probably get an error message. Sometimes I find I have to delete and replace the input and output blocks from the IC2 section of the toolbox. 
 5) Go back to the config page and delete IC1. If all the objects were changed then it will let you delete it. If something was missed, then it will not let you delete it. 
 Regards, 
 Harish)

Harishgowtham · Answer

Hello Matthias, 
 matzzee said: I had a look at the SERIAL_PORTS setting. 
 For outputs, all settings are the same (at least for the serial output ports that i use). 
 The above-mentioned steps will only shift the entire schematic from one IC to another. For the hardware registers, you have to set it newly for the ADAU1466. 
 matzzee said: The signals on the inputs seem to be differently routed from HW into DSP, and regarding outputs, the pins are also different (changed connections towards DAC) 
 For the serial input and output channels also, you have to set the respective channels again in the schematic. Only your entire processing blocks would remain the same as your old IC. 
 matzzee said: The signals on the inputs seem to be differently routed from HW into DSP 
 Are you talking about the serial input port blocks in the schematic? 
 For the input/output blocks and the hardware registers page, we have to take care of our own and set those again. 
 Did I answer your question? If not, then please explain your issue a bit more. 
 Regards, 
 Harish

Harishgowtham · Answer

Hello Matthias, 
 Let me investigate and get back to you. 
 Regards, 
 Harish

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USB communication failure on filter parameter-change