Daqctl

daqctl is a userspace driver utility to manage the data acquisition core in the FPGA.

xuartctl

File:Daqctl-diagram.png

Overview

Using daqctl you can have data acquisition control over TCP. The core allows you to set 2 different frequencies

Usage

Help

 Usage: daqctl [OPTION] ...
 Technologic Systems ADC-7558 core userspace driver utility.
 Example: daqctl --server --speed=13khz --chan=0-3,5,7 --gain2x=5
 
 -i, --irq=N            Use IRQ N as ADC IRQ (30)
 -s, --speed=FREQ       Use FREQ as default sample frequency (1000)
 -c, --chan=CHANS       Sample only channels CHANS (0-15)
 -x, --exttrig=PIN      Override --speed and use external trigger instead
 -g, --gain2x=CHANS     Use high-gain setting on CHANS
 -l, --cloop=CHANS      Enable 4-20 ma current loops on CHANS
 -d, --server           Daemonize and run as server
 -I, --bind=IPADDR      Bind server to IPADDR
 -p, --connect=HOST     Connect to remote daqctl service at HOST
 -P, --dumpcsv          Output acquired samples as CSV text
 -b, --dumpbin          Output acquired samples as raw binary
 -1, --single           Print one sample's values
 -D, --pwm=PWMSPEC      Sets PWM outputs according to PWMSPEC
 -h, --help             This help
 
 --irq-on-change=PIN    Flush when digital input PIN (0-7) changes
 --irq-on-glitch=PIN    Flush when digital input PIN (0-7) glitches
 --irq-on-high=PIN      Flush while digital input PIN (0-7) is high
 --irq-on-low=PIN       Flush while digital input PIN (0-7) is low
 --irq-on-quadrature    Flush when a quadrature counter changes value
 --irq-on-quad-dir      Flush when quadrature changes direction
 --irq-on-counter       Flush when a monitored edge counter changes
 --irq-on-any-change    Flush when any digital input changes
 --max-irq-rate=NSAM    IRQ at most every NSAM (1,4,16,64) samples
 --max-irq-rate-always  Always interrupt at max rate
 --min-irq-rate=HZ      Minimum IRQ rate HZ (1000,500,100,0)
 --min-irq-rate-always  Always interrupt at min rate

Examples

Even without writing code, you can do simple operations like sampling ADC or controlling the PWM channels.

For sampling ADC to a CSV file:

daqctl -c 1-4 -P

Turn all 7 PWM channels (0-6) off (0% duty) (OUT1-OUT4 external and pins 23, 21, and 25 on the JTAG header) and set default PWM

daqctl --pwm=0-6:0%@100hz

Programming with libdaqctl

We provide a library for the end user called libdaqctl that you can use to interact with the daqctl TCP server.

[libdaqctl.c] [libdaqctl.h]

This board has one timer that you can easily set by ms or hz, and you can set the duty cycle by hz or percent. The configurable timer will support a maximum 131071hz. If you need another timer you can also use the ADC sample rate which is a static 2khz. You can use this by 'OR'ing in the value with the duty cycle.

 Note:  If you change the PWM frequency for one channel 
 with the configurable timer, it will change it for any other channels using it.

Variable and ADC sample rates

This example shows using the configurable frequency and the ADC sample frequency on different channels, as well as sampling ADC channels 1 and 2.

#include <stdio.h>
#include <strings.h>

#include "libdaqctl.h"

void daq_print(struct daqctl *dq)
{
        int i;

        for(i = 3; i < 5; i++)
        {
                printf("chan%i=%i\n", i, dq->last[i]);
        }
}

int main(int argc, char **argv)
{
        int sk;
        int i;
        struct daqctl dq;
        bzero(&dq, sizeof(dq));

        // You can pass any arguments as you could to 
        // the daqctl application here.  This example only samples 
        // ADC channels 1 and 2
        sk = daqctl_connect("127.0.0.1", "--chan=4-5");

        // Set channel 0 to 1khz with a duty cycle of 500khz
        daqctl_setoutput(sk, 0, PWM_FREQ(0x1000) | PWM_DUTY(0x500));

        // Set channel 1 to 2khz from ADC core
        daqctl_setoutput(sk, 1, PWM_DUTY_PCT(100) | PWM_FREQ_IS_SAMPLERATE);

        for(;;)
        {
                dq.fd = sk;
                daqctl_process(&dq);
                daq_print(&dq);
        }
}

Controlling a Servo

In this example I've wired 5v in to OUT1+ (from JTAG pin 26 on the TS-7558), as well as the servo's + wire. OUT- and servo- are connected, and the servo's GND is plugged into one of the ground connectors in P2. The desired behavior is that the servo will rotate back and forth between maximum and minimum and reverting to neutral when a ctrl+c / SIGINT is sent to the application.

#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <signal.h>
#include "libdaqctl.h"

int sigint_rec = 0;

void sigint_cb(int sig);

int main(int argc, char **argv)
{
	char *host;
	if(argc < 2)
		host = "127.0.0.1";
	else
		host = argv[1];

	int daqfd = daqctl_connect(
		host,
		"--pwm=0:100%@20ms");
	assert(daqfd != 0);

	signal(SIGINT, sigint_cb);

	for(;;)
	{
		printf("Maximum\n");
		daqctl_setoutput(daqfd, 0, PWM_DUTY(0x199)); // 2ms
		sleep(1);

		if(sigint_rec)
			break;

		printf("Minimum\n");
		daqctl_setoutput(daqfd, 0, PWM_DUTY(0x51)); // 1ms
		sleep(1);

		if(sigint_rec)
			break;
	}

	printf("Neutral\n");
	daqctl_setoutput(daqfd, 0, PWM_DUTY(0xF5)); // 1.5ms
	sleep(1);

	close(daqfd);

	return 0;
}

void sigint_cb(int sig)
{
	sigint_rec = 1;
}