USB spec limits bulk endpoints to 64 byte payload max.

For full-speed devices, bulk endpoints may use 8, 16, 32 or 64 bytes, but no
more.

diff --git a/ao_usb.h b/ao_usb.h
index 9356c8580ce809aaca545cc6713167c0e53cbe11..6633dafc7809763ffb23ebae1fa508e506f0b536 100644 (file)
--- a/ao_usb.h
+++ b/ao_usb.h
@@ -68,9 +68,12 @@
 /*
  * Double buffer IN and OUT EPs, so each
  * gets half of the available space
+ *
+ * Ah, but USB bulk packets can only come in 8, 16, 32 and 64
+ * byte sizes, so we'll use 64 for everything
  */
-#define AO_USB_IN_SIZE         256
-#define AO_USB_OUT_SIZE                128
+#define AO_USB_IN_SIZE         64
+#define AO_USB_OUT_SIZE                64
 
 #define AO_USB_EP0_IDLE                0
 #define AO_USB_EP0_DATA_IN     1