1 files changed, 33 insertions, 0 deletions

diff --git a/usb_extra.c b/usb_extra.c
new file mode 100644
index 000000000..94c317d98
--- /dev/null
+++ b/usb_extra.c
@@ -0,0 +1,33 @@
+#include <avr/interrupt.h>
+#include "usb_extra.h"
+
+int8_t usb_extra_send(uint8_t bits)
+{
+        uint8_t intr_state, timeout;
+
+        if (!usb_configured()) return -1;
+        intr_state = SREG;
+        cli();
+        UENUM = EXTRA_ENDPOINT;
+        timeout = UDFNUML + 50;
+        while (1) {
+                // are we ready to transmit?
+                if (UEINTX & (1<<RWAL)) break;
+                SREG = intr_state;
+                // has the USB gone offline?
+                if (!usb_configured()) return -1;
+                // have we waited too long?
+                if (UDFNUML == timeout) return -1;
+                // get ready to try checking again
+                intr_state = SREG;
+                cli();
+                UENUM = EXTRA_ENDPOINT;
+        }
+
+        UEDATX = 1; // report id
+        UEDATX = bits;
+
+        UEINTX = 0x3A;
+        SREG = intr_state;
+        return 0;
+}