expand the test program

main.c

@@ -1,32 +1,90 @@
 #include <stdio.h>
 #include <unistd.h>
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
 #include "uvosled.h"
 
+void print_help(const char* progname)
+{
+	printf("UVOS usb led test application\n");
+	printf("usage: %s [OPERATION] [CHANNEL] [VALUE]\n", progname);
+	printf("available operations: set on off help\n");
+}
+
 int main(int argc, char* argv[])
 {
+	if(argc < 2 || strcmp (argv[1], "help") == 0)
+	{
+		print_help(argv[0]);
+		return 0;
+	} 
+	
 	struct uvosled led;
 	
 	if(uvosled_connect(&led))
 	{
-		printf("cant connect \n");
+		printf("Can not connect to UVOS usbled device\n");
 		return -1;
 	}
-	if(uvosled_poweron(&led))
+	
+	if(strcmp(argv[1], "on") == 0)
 	{
-		printf("cant power on \n");
+		if(uvosled_poweron(&led))
-		return -2;
+			printf("cant power on \n");
 	}
-	if(uvosled_set_current(&led, CHANNEL_A | CHANNEL_B  , 0.5))
+	else if(strcmp(argv[1], "off") == 0)
 	{
-		printf("cant set current \n");
+		uvosled_set_current(&led, 0xff , 0);
-		return -3;
+		uvosled_poweroff(&led);
 	}
-	sleep(30);
+	else if(strcmp(argv[1], "set") == 0)
-	if(uvosled_set_current(&led, CHANNEL_A | CHANNEL_B , 0))
 	{
-		printf("cant set current \n");
+		if(argc != 4)
-		return -3;
+		{
+			print_help(argv[0]);
+			return 0;
+		}
+		
+		uint8_t mask = 0;
+		
+		switch(argv[2][0])
+		{
+			case 'a':
+			case 'A':
+			case '1':
+				mask = CHANNEL_A;
+				break;
+			case 'b':
+			case 'B':
+			case '2':
+				mask = CHANNEL_B;
+				break;
+			case 'c':
+			case 'C':
+			case '3':
+				mask = CHANNEL_C;
+				break;
+			case 'd':
+			case 'D':
+			case '4':
+				mask = CHANNEL_D;
+				break;
+			default:
+ 				printf("A channel must be selected out of A, B, C or D\n");
+		}
+		
+		if(mask)
+		{
+			char* end;
+			float value = strtof(argv[3], &end);
+			if(isnan(value) || value < 0 || value > 1.0f)
+				printf("A channel value between 0 and 1.0 must be supplied\n");
+			else if(uvosled_set_current(&led, mask, value))
+				printf("Failed to set current\n");
+		}
 	}
+	
 	uvosled_poweroff(&led);
 	uvosled_disconnect(&led);
 	return 0;

uvosled.h

@@ -15,23 +15,29 @@ struct uvosled {
 	struct usbshm* priv;
 };
 
+// returns 0 on sucess and < 0 on failure
 int uvosled_connect(struct uvosled* led);
 
 // power on cameras
+// returns 0 on sucess and < 0 on failure
 int uvosled_poweron(struct uvosled* led);
 
 // power off cameras
+// returns 0 on sucess and < 0 on failure
 int uvosled_poweroff(struct uvosled* led);
 
 // channels is a mask of bits, you can set it like this: CHANNEL_A | CHANNEL_C to activate channels A and C
-// current is in Ampere
+// current is in percent of the values selected by the linear regulator resistors
+// returns 0 on sucess and < 0 on failure
 int uvosled_set_current(struct uvosled* led, uint8_t channels, float current);
 
 // causes the cameras to take an image
+// returns 0 on sucess and < 0 on failure
 int uvosled_trigger(struct uvosled* led);
 
 // leds are lit for time seconds and the camera is activated cameraOffset seconds after they are lit
 // real time guarenteed by microcontroller
+// returns 0 on sucess and < 0 on failure
 int uvosled_capture(struct uvosled* led, int channels, float current, double time, double cameraOffset);
 
 void uvosled_disconnect(struct uvosled* led);