[ts-7000] Help pls: TS-ADC24 is freezing during data acquisition

["Alex" <>]

Hi guys,

I am wondering if anybody had any luck with making TS-ADC24 work with high 
sampling rates?

I use TS-ADC24 to sample 4 channels at 200kHz, it runs for few minutes and then 
the application is freezing.  The application (and board) runs fine at 50 kHz.  
If I increase sampling rate to 250kHz, the board is freezing in few seconds. 
(According to TS-ADC24 specs, the card should be able to collect 4 channels @ 
500 kHz)

I can understand occasional FIFO buffer overflow, but the fact that the board 
is simply freezing and does not return anything seems to me like a major flaw 
is TS design.  

Did anybody experience same problem or has any suggestions how I can deal with 
TS-ADC24 freezing? 

For a reference, below is code that is responsible for data acquisition.


#define ADC_START_MSK 0x0001
...

ADC_CFG = ADC_BASEIO + 0x02; // Configuration register
ADC_STAT = ADC_BASEIO + 0x08; // Status register

...

int n_Success = 1;
unsigned long i = 0;
unsigned short val = 0;
int n_Priority = -21;
int which = PRIO_PROCESS;
id_t pid;
int n_Result = 0;

// Change priority to -20
pid = getpid();
n_Priority = -20;
n_Result = setpriority(which, pid, n_Priority);

// Start ADC acquisition        
POKE16((unsigned long)(ADC_CFG), (PEEK16((unsigned long) (ADC_CFG)) | 
ADC_START_MSK));

while(i < n_Length)
{
    // Read the status register
    val = PEEK16((unsigned long) (ADC_STAT));
    if ((val & 0xFFC0)) // leave the most recent sample in FIFO
    {
        // Test for overflow
        if ((val & 0x8000))
        {
            // if there is overflow, exit loop
            n_Success = -1;
            i = n_Length;
        }
        else
        {
            n_Samples[i++] = PEEK16((unsigned long) (ADC_FIFO));
        }
    }
}

// stop ADC system
// = set bit 0 to 0
POKE16((unsigned long)(ADC_CFG), (PEEK16((unsigned long) (ADC_CFG)) & 
~ADC_START_MSK));

// Empty FIFO
while(((PEEK16((unsigned long) (ADC_STAT)) & 0xFFC0) >> 6) > 0)
{
    val = PEEK16((unsigned long) (ADC_FIFO));                   
}

//Restore priority to 0
n_Priority = 0; 
n_Result = setpriority(which, pid, n_Priority); 
        



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