add usbtmc_status

diff --git a/usbtmc.c b/usbtmc.c
index 4a23a4fad953da902da62f41ea6d8563e9137a53..419d100069b25111e57c7ab9b94abea9d81fe11f 100644 (file)
--- a/usbtmc.c
+++ b/usbtmc.c
@@ -59,6 +59,22 @@ static struct scope* usbtmc_find_scope() {
        return NULL;
 }
 
+unsigned char usbtmc_status(struct scope *sc)
+{
+       int r;
+       unsigned char status[3];
+
+       sc->usb.bTag++;
+
+       r = usb_control_msg(sc->usb.dev, 0xA1, 128, (sc->usb.bTag & 0x7f), 0, (char*)status, 3, USB_TIMEOUT);
+       if ((r != 3) || (status[0] != 0x01) || (status[1] != (sc->usb.bTag & 0x7f))) {
+               printf("READ_STATUS_BYTE failed: %d 0x%x 0x%x 0x%x\n", r, status[0], status[1], status[2]);
+               return 0xff;
+       }
+
+       return status[2];
+}
+
 /*
  * Send a scpi-command to the scope. The response goes into the buffer
  * called resp, with a size of resplen. If resp==NULL, no response