Add example for SRS DS345

Justfile

@@ -28,9 +28,17 @@ outdated:
   go list -u -m all
 
 # Run the ASRL Keysight E3631A power supply example application.
-ex1 port:
+e3631a port:
   #!/usr/bin/env bash
   echo '# ASRL Keysight E3631A Example Application'
   cd {{justfile_directory()}}/examples/keysight/e3631a
   env go build -o e3631a
   ./e3631a -port={{port}}
+
+# Run the ASRL Keysight E3631A power supply example application.
+ds345 port:
+  #!/usr/bin/env bash
+  echo '# ASRL SRS DS345 Example Application'
+  cd {{justfile_directory()}}/examples/srs/ds345
+  env go build -o ds345
+  ./ds345 -port={{port}}

examples/srs/ds345/main.go

@@ -0,0 +1,79 @@
+// Copyright (c) 2020–2024 The prologix developers. All rights reserved.
+// Project site: https://github.com/gotmc/prologix
+// Use of this source code is governed by a MIT-style license that
+// can be found in the LICENSE.txt file for the project.
+
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"time"
+
+	"github.com/gotmc/asrl"
+)
+
+var (
+	serialPort string
+	baudRate   int
+)
+
+func init() {
+
+	// Get serial port for DS345.
+	flag.StringVar(
+		&serialPort,
+		"port",
+		"/dev/tty.usbserial-PX8X3YR6",
+		"Serial port for DS345",
+	)
+
+	flag.IntVar(&baudRate, "baud", 9600, "Baud rate")
+}
+
+func main() {
+	// Parse the flags
+	flag.Parse()
+
+	// Open virtual comm port.
+	address := fmt.Sprintf("ASRL::%s::%d::8N2::INSTR", serialPort, baudRate)
+	log.Printf("VISA Address = %s", address)
+	dev, err := asrl.NewDevice(address)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer dev.Close()
+
+	// Query the identification of the function generator.
+	idn, err := dev.Query("*idn?")
+	if err != nil && err != io.EOF {
+		log.Fatalf("error querying serial port: %s", err)
+	}
+	log.Printf("query idn = %s", idn)
+
+	// Send commands to the function generator required to create a coded carrier
+	// operating at 100 Hz with 400 ms on time and 200 ms off time.
+	cmds := []string{
+		"MENA0",      // Disable modulation
+		"FUNC 0",     // Set output function to sine wave
+		"FREQ 100.0", // Set frequency to 100 Hz
+		"AMPL 0.5VP", // Set the amplitude to 0.5 Vpp
+		"OFFS 0.0",   // Set the offset to 0 Vdc
+		"PHSE 0.0",   // Set the phase to 0 degrees
+		"BCNT 40",    // Set burst count to 40 (rounded to nearest integer)
+		"TSRC1",      // Use internal trigger
+		"TRAT 1.667", // Set the trigger rate to 1.667 Hz
+		"MTYP5",      // Set the modulation to burst
+		"MENA1",      // Enable modulation
+	}
+	for _, cmd := range cmds {
+		log.Printf("Sending command: %s", cmd)
+		err = dev.Command(cmd)
+		if err != nil {
+			log.Fatal(err)
+		}
+		time.Sleep(250 * time.Millisecond)
+	}
+}