diff --git a/firmware/smbusb_firmware.c b/firmware/smbusb_firmware.c
index ff06212..6fdfe74 100644
--- a/firmware/smbusb_firmware.c
+++ b/firmware/smbusb_firmware.c
@@ -840,7 +840,7 @@ BOOL handle_vendorcommand(BYTE cmd) {
 }
   
 
-void timer0_isr() __interrupt TF0_ISR {
+void timer0_isr() __interrupt (TF0_ISR) {
  count++;
 }
 
@@ -876,16 +876,16 @@ BOOL handle_set_configuration(BYTE cfg) {
 }
 
 
-void sudav_isr() __interrupt SUDAV_ISR {
+void sudav_isr() __interrupt (SUDAV_ISR) {
  dosud=TRUE;
  CLEAR_SUDAV();
 }
 
-void usbreset_isr() __interrupt USBRESET_ISR {
+void usbreset_isr() __interrupt (USBRESET_ISR) {
  handle_hispeed(FALSE);
  CLEAR_USBRESET();
 }
-void hispeed_isr() __interrupt HISPEED_ISR {
+void hispeed_isr() __interrupt (HISPEED_ISR) {
  handle_hispeed(TRUE);
  CLEAR_HISPEED();
 }