diff --git a/cmdline/read-temp.c b/cmdline/read-temp.c
index 139a165..c6aa9e7 100644
--- a/cmdline/read-temp.c
+++ b/cmdline/read-temp.c
@@ -26,6 +26,10 @@ respectively.
 
 #include "../firmware/masterchip/usbdrv/usbconfig.h"  /* device's VID/PID and names */
 
+void usage() {
+	printf("Usage: read-temp [spi|temp] [opcode] [addr] [value]\n");
+}
+
 int main(int argc, char **argv)
 {
 usb_dev_handle      *handle = NULL;
@@ -41,6 +45,7 @@ int                 cnt, vid, pid;
     /* The following function is in opendevice.c: */
     if(usbOpenDevice(&handle, vid, vendor, pid, product, NULL, NULL, NULL) != 0){
         fprintf(stderr, "Could not find USB device \"%s\" with vid=0x%x pid=0x%x\n", product, vid, pid);
+		usage();
         exit(1);
     }
     /* Since we use only control endpoint 0, we don't need to choose a
@@ -66,44 +71,50 @@ int                 cnt, vid, pid;
 #endif
     int rxValue, rxIndex;
     int value = 0, index = 0;
-
+	
     if(strcasecmp(argv[1], "temp") == 0) {
-      int i=0;
-      cnt = usb_control_msg(handle, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_ENDPOINT_IN, 100, value, index, buffer, sizeof(buffer), 5000);
-      if(cnt < 0){
-	fprintf(stderr, "\nUSB error in iteration %d: %s\n", i, usb_strerror());
-      }
-      rxValue = ((int)buffer[1] & 0xff) | (((int)buffer[0] & 0xff) << 8);
-      rxIndex = ((int)buffer[3] & 0xff) | (((int)buffer[2] & 0xff) << 8);
-      fprintf(stderr, "%3d.%02d*C ", rxValue/100, rxValue%100);
-      fprintf(stderr, "%3d.%02d*C \n", rxIndex/100, rxIndex%100);
-      
-      cnt = usb_control_msg(handle, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_ENDPOINT_IN, 101, value, index, buffer, sizeof(buffer), 5000);
-      if(cnt < 0){
-	fprintf(stderr, "\nUSB error in iteration %d: %s\n", i, usb_strerror());
-      }
-      rxValue = ((int)buffer[1] & 0xff) | (((int)buffer[0] & 0xff) << 8);
-      rxIndex = ((int)buffer[3] & 0xff) | (((int)buffer[2] & 0xff) << 8);
-      fprintf(stderr, "%3d.%02d*C ", rxValue/100, rxValue%100);
-      fprintf(stderr, "%3d.%02d*C \n", rxIndex/100, rxIndex%100);
+		int i=0;
+		cnt = usb_control_msg(handle, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_ENDPOINT_IN, 100, value, index, buffer, sizeof(buffer), 5000);
+		if(cnt < 0){
+			fprintf(stderr, "\nUSB error in iteration %d: %s\n", i, usb_strerror());
+		}
+		rxValue = ((int)buffer[1] & 0xff) | (((int)buffer[0] & 0xff) << 8);
+		rxIndex = ((int)buffer[3] & 0xff) | (((int)buffer[2] & 0xff) << 8);
+		fprintf(stderr, "%3d.%02d*C ", rxValue/100, rxValue%100);
+		fprintf(stderr, "%3d.%02d*C \n", rxIndex/100, rxIndex%100);
+		
+		cnt = usb_control_msg(handle, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_ENDPOINT_IN, 101, value, index, buffer, sizeof(buffer), 5000);
+		if(cnt < 0){
+			fprintf(stderr, "\nUSB error in iteration %d: %s\n", i, usb_strerror());
+		}
+		rxValue = ((int)buffer[1] & 0xff) | (((int)buffer[0] & 0xff) << 8);
+		rxIndex = ((int)buffer[3] & 0xff) | (((int)buffer[2] & 0xff) << 8);
+		fprintf(stderr, "%3d.%02d*C ", rxValue/100, rxValue%100);
+		fprintf(stderr, "%3d.%02d*C \n", rxIndex/100, rxIndex%100);
+    } else if(strcasecmp(argv[1], "spi") == 0) {
+		if(argc != 5) {
+			usage();
+			return 0;
+		}
+		int opcode, addr, value;
+		int i=0;
+		opcode = atoi(argv[2]);
+		addr = atoi(argv[3]);
+		value = atoi(argv[4]);
+		
+		cnt = usb_control_msg(handle, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_ENDPOINT_IN, opcode, addr, value, buffer, sizeof(buffer), 5000);
+		if(cnt < 0){
+			fprintf(stderr, "\nUSB error in iteration %d: %s\n", i, usb_strerror());
+		}
+		rxValue = ((int)buffer[1] & 0xff) | (((int)buffer[0] & 0xff) << 8);
+		rxIndex = ((int)buffer[3] & 0xff) | (((int)buffer[2] & 0xff) << 8);
+		
+		fprintf(stderr, "request = 0x%04x\n", opcode);
+		fprintf(stderr, "rxValue = 0x%04x value = 0x%04x\n", rxValue, addr);
+		fprintf(stderr, "rxIndex = 0x%04x index = 0x%04x\n", rxIndex, value);	  
     } else {
-      int opcode, addr, value;
-      int i=0;
-      sscanf(argv[1], "%i %i %i", &opcode, &addr, &value);
-      cnt = usb_control_msg(handle, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_ENDPOINT_IN, opcode, addr, value, buffer, sizeof(buffer), 5000);
-      if(cnt < 0){
-	fprintf(stderr, "\nUSB error in iteration %d: %s\n", i, usb_strerror());
-      }
-      rxValue = ((int)buffer[1] & 0xff) | (((int)buffer[0] & 0xff) << 8);
-      rxIndex = ((int)buffer[3] & 0xff) | (((int)buffer[2] & 0xff) << 8);
-      
-      fprintf(stderr, "request = 0x%04x\n", opcode);
-      fprintf(stderr, "rxValue = 0x%04x value = 0x%04x\n", rxValue, addr);
-      fprintf(stderr, "rxIndex = 0x%04x index = 0x%04x\n", rxIndex, value);
-      
-    }
-
-
+		usage();
+	}
 
     usb_close(handle);
     return 0;