ADAS3022 Arduino example code for all channel reading we need

Question

Hi, 
 we are working ADAS3022EDZ Eval board to communicate SPI through Arduino board. please help me

@skowalik · Accepted Answer

bakyaraj, 
 During configuration I write the configuration onto MOSI (SDI) on the first conversion serial transfer and then execute two more conversions with data accesses with 0x0000 passed to the device such that no further updates to the configuration word are requested. This ensures that the NEXT conversion started will give me the result (in this case) of channel 0-1, followed by the difference of channels 2-3, then channels 4-5, channels 6-7 and so on as I loop the data capture. 
 During data capture I always send 0x0000 to avoid updating the configuration word. 
 In all my setups RESET = 0, PD = 0 so I did not capture them. 
 Sean

bakyaraj · Answer

my SPI configuration is SPI mode0 and CPHA =0 and CPOL =1 . now we changed update you

@skowalik · Answer

Bakyaraj, 
 As Jellenie accurately summarized we don't have any prepared example code for reference for the Arduino IDE that you could use directly. Depending on your sampling requirements we may be able to make suggestions as to how you might quickly prototype some code that will allow you to get started but which we can't guarantee will work over all conditions. To that end can you let me know the following. 
 1) How quickly do you intend to sample each channel? Please note that depending on your chosen Arduino target you are going to be limited to a fraction of the full data throughput. 
 2) Just to verify you are going to be using the multiplexed ADAS3022 and not the simultaneous sampling ADAS3023. 
 3) Assuming you are using the ADAS3022 are you planning on: 
 
 Using either the simple or advanced sequencer functions? 
 Sampling temperature or the auxiliary channel input in sequencer mode? 
 Alternatively do you want to be able to update the configuration on every conversion? 
 
 4) Which Arduino product are you using? Uno/Due other. 
 To get you started while you get back to me with specifics to the questions above I would recommend familiarizing yourself with the following. 
 1) The SPI Library and specifically using the Interrupt driven call 
 2) There are a number of Timer libraries available that would allow generation of the convert start signal which you could then also use to generate a spi transaction from within the same code for asynchronous operation or you could use the BUSY pin as an interrupt to synchronously trigger the spi transaction. 
 Anyways if you can prepare some answers to the question and get back to me we can at least attempt to put together a prototype flow that allows you to get started on development from a concept perspective with respect to connectivity and a state flow diagram. However, on the code side you'll need to rely a bit more on the Arduino users as the experts on how to implement the solution to optimize the conversion rate. 
 Sean

@skowalik · Answer

bakyaraj, 
 
 1) It looks like you attempted to implement the configuration sequence but you did not allow the conversion to complete before you started the rest of your data capture. If you have a us timer I would recommend adding a wait 1us between your clear_conversion(); statement and the readback. 
 bakyaraj said: // Configure Device 
 
 ADAS3022_Set_Conversion (); 
 ADAS3022_Clear_Conversion (); 
 
 gioSetBit ( spiPORT3 , 0 , 0 ); 
 
 spiTransmitAndReceiveData ( spiREG3 , & dataconfig1_t , 8 , HV_SPI_TX_Data_Master ,& HV_SPI_RX_Data_Master [ 0 ]); 
 
 gioSetBit ( spiPORT3 , 0 , 1 ); 
 
 //DUMMY CONVERSIONS 
 /*0-1*/ 
 ADAS3022_Set_Conversion (); 
 ADAS3022_Clear_Conversion (); 
 
 ADAS3022_Set_Conversion (); 
 ADAS3022_Clear_Conversion (); 
 
 2) Similarly in the channel code you'll need to add a wait or use busy going low as an interrupt to either asynchronously or synchronously time the transmission of the data word after convert start. 
 bakyaraj said: /*1-2*/ 
 ADAS3022_Set_Conversion (); 
 ADAS3022_Clear_Conversion (); 
 
 gioSetBit ( spiPORT3 , 0 , 0 ); 
 
 spiTransmitAndReceiveData ( spiREG3 , & dataconfig1_t , 1 , HV_SPI_TX_Data_Master_1 ,& HV_SPI_RX_Data_Master [ 2 ]); 
 
 HV_SPI_Voltage [ 1 ] = ( float ) (((( float ) HV_SPI_RX_Data_Master [ 2 ] / 32768.0 ) * INPUT_VOLTAGE_RANGE )); 
 
 gioSetBit ( spiPORT3 , 0 , 1 );

3) Finally I would recommend you verify your code conversion statement is correct such that the 16-bit signed data is correctly interpreted to generate signed integers. Given the float type I'm concerned the code will interpret the output at 0-65535 instead of -32768 to 32767. You can probably fix that by changing the inner cast statement to signed 16 bit integer cast and then float around that information when you do the divide by 16. I don't have an Arduino IDE or interpreter installed myself so I can't verify that I'm 100% correct but it should be easy for you to do so. 
 Hope that helps 
 
 Sean

@skowalik · Answer

bakyaraj, 
 One thing I noticed and forgot to mention last time I responded was to change your SPI mode to MODE 0, CPHA = 0, CPOL = 0. 
 I will be on holiday over the balance of the week but I'm going to ask a colleague to watch this thread. Please included updated timing diagrams of your code execution if the SPI Mode trick doesn't fix your readback. Please also indicate what your input conditions are so that we can help assess the trouble you are seeing. 
 Sean

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ADAS3022 Arduino example code for all channel reading we need

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