This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

HELP Interfacing DSK 6416 + ADS1174EVM + DAC8554EVM

Other Parts Discussed in Thread: DAC8554EVM, DAC8554, ADS1274, ADS1174, ADS1147

My name is Ivan and I am a researcher that works in a Neurosciences Lab with biological signals.


I write directly to you because I haven´t been able to post anything on the TI forum and I have been three days now and I am unable to do it.  I have tried many times to do it from different places and browsers and when I click on post it gets stuck and stays there forever. Although I know this is not the normal procedure I hope you can help me with some problems I have regarding TI ADC/DAC converters and equipment since I am a complete novice in DSP.

We have an undergoing project for which we need a system that is able to receive a signal, process it and output in Real Time. We work with a range of frequencies that go from DC to 1000 Hz. So basically the flow would be ADC - DSP - DAC. We decided to build a modular system with a TI DSP. We bought a DSK TMS320C6416 for the processing. It already has an audio code but it filters the low frequency signals so we bought a 5-6K interface card and a ADS1174EVM and DAC8554EVM modules that are able to perform ADS-DAC conversion of low frequency signals.

Up to here, the system should be able to input a signal through the ADS1174EVM, process it in with the C6416 and output with the DAC8554EVM all in Real Time, isn´t it?.

The problem is that I am finding big problems and I am not able to make the whole system work:

1- I do know know how to connect the modules and pins in order to make it work. What about the external power that to feed the ADCs and DAC. Is there any documentation where I can take as a reference?. Could you orientate me?

2- Once everything is connected, I haven´t found any docs that make reference to the C6416 and these converters. Only some interfacing of some other ADCs and the C6713. I would like to be able to take some samples with the ADC and to output them with the DAC, just this simple operation but it seems impossible to me now. Is there any code regarding this?. I don´t, how could I do it? Maybe most of the code from the C6713 examples can be used changed for the C6416?. Are there any examples od DAC conversion with a similar system as the one I have?.

We are opened also to receive advice about other systems that could be more suitable for our purpose and more easy to work with them. Is there any other or more suitable device of TI that could do alone what we need?.

I hope you can help me with this matter since I am completely lost at this point.

Thanks in advance.

Iván

  • Hi Ivan,

    From the hardware side of things, the ADS1174EVM would have to be mounted on the 5-6K Interface board at connectors J10, JP6 and J16.  Take care not to miss-align the female sockets of the EVM to the male pins on the interface board.  The DAC8554EVM would need to be mounted on J12, JP5 and J15 of the interface board.  JP5 and JP6 are the power supply connectors to the EVM's.  These are fed from the screw terminals along the edge of the 5-6K Interface board.

    I'm not aware of any code examples specifically written for the C6416 with the ADS1174EVM, but there is a sample project for the ADS1274 on our 'Design Notes' tab from the Precision Data Converter forum.  There is an example project there for the DAC8554 as well.  Please review them here:

    http://e2e.ti.com/support/data_converters/precision_data_converters/w/design_notes/1223.examples-for-the-tms320c6400-dsp-platform.aspx 

     

  • Dear Tom,

    Thank you very much for your answer. I think I should be able to try it with the examples you pointed me.

    I have other questions, these regarding from one side the working range or the ADC/DAC and the pins.

    1- ¿How do the pins have to be set in the EVM Modules and the 5-6K in order everything to work properly?

    2- ¿What is the input range of the ADS1274 in this case?. We work with signals that might go from -2 to 2 volts.

    What is the output range for the DAC8554?.

    Thanks,

    Iván.

  • Hi Ivan,

    1.  The main.c files for both projects describe the jumper settings needed on the hardware.

    2.  The input and output range of the ADS1174 and DAC8554 are both listed in their respective data sheets.  The ADS1147 can accept inputs from 0-5V and the DAC8554 will output 0-5V.  If you have a bipolar input, you will need to put it through a level shifting circuit first.

  • Dear Tom,
    I have been checking the main.c of the DAC8554 program and I have some doubts regarding the pin configurations. 
    W7, W8, W9, W10 (closed). What does it mean by closed?. There are three pins per W* so the possibilites are 1-2 or 2-3.
    connect J6.1 with J6.3 (Vcc = +5VA) 

    connect J6.5 with J6.6 (connect AGND and DGND) 

    connect J5.1 with J5.3 (Vdd = +5VA)

    I can't find J6 & J5. Where are they located?
    do I have to provide also +15/-15  through J1?
    From the other side and regarding the ADS1274 program. Should it work straight or I maybe have to modify something?. For example there are some files that have the header *1274* like t1274_fn.h . These ones and the config files should be ok for the 1174 or I have to create new ones specific for it?. In such a case is there a tool that could help me? I see that the H/W interface was created with the Data Converter Support. Checking here (http://www.ti.com/tool/dcpfreetool) I don't find the neither the 1174 nor the 1274.
    Thanks again.
    Ivan
  • Hi Ivan,

    Sorry about that, it looks like the code was written with a pre-release version of the EVM, let me see what I can do to clarify that.  I'll need to look up some old files, so I'll get back to you ASAP.

  • Perfect Tom,

    I wait for your reply.

    Thanks,

    Ivan

  • Hi Ivan,

    The original DAC8554 board schematic is attached here.  Jumpers W10 - W7 correspond to JMP 1-4 respectively.

    DAC8554_sch.pdf
  • Hi Tom,

    I have checked the old schematic and compared with the new. After setting all the pings correctly I still do not get anything.

     connect J5.1 with J5.3  (Vdd = +5VA)  

    J5 does  not appear in the old schematic neither.

    The pins in the 5-6k card look ok also.

    What i just do if to load the compiled project into the DSK and excute it. I connect the J4.2 out (I tried all the outputs) to an oscilloscope and see nothing.

    What could be happening?.

    In the main.c it does not mention the +15,-15 analog supply. Is it missing?

    Regards,

    Ivan

  • Hi Tom,

    I am trying to set up the pins to ADS1274 program. It seems it was done with an old version and some of the pins are not in the ADS1174EVM I have.

    J18 1-2

    there are only 2 pins in J18 on the board I have (and no connector on them). Looking at the doc it does not make a lot of sense to connect them together.

    S2 - S9: AMP (right / up)

    I only have until S5

    Could you help me with the correct set up of the pins?.

    Thanks,

  • Hi Ivan,

    Sorry for the slow response - I am on business travel this week.  I need to look at the actual hardware to help you decipher this, so it will be next Tuesday before I can assist you further.

  • Hi Ivan,

    For the DAC, J3 in the new schematic corresponds to J6 in the old one, and yes, you do need the Vcc/Vss (+/-15V) to generate the reference as well as power the output amplifier.  J18 is intended as a means for you to apply an external conversion clock.  Pin 1 is GND and pin2 is where you would apply a clock source via signal generator.  From the VC6416DSK, you could also use a TIMER function by closing J17.

  • Hi Tom,

    I am trying to configure the ADS1174 now. I downloaded the program that you linked to me but it does not work. I do not know if it is because it was designed for the ADS1274 and I have to change somethings or because I am doing something wrong. I saw that the 1274 was configured with the DC plugin tool. The problem is that the 1174 is not among the devices listed by the application. So, how could I set up the config of the adc?. Besides, the program was developed to run on the DSK6416 with a chip of 600Mhz, and the new one runs at 1Ghz. Is there anything I have to change about this?.

    How are the steps to configure this from the scratch?.

    Thanks.