diff --git a/avr/modules/uart_hw/defs.asm b/avr/modules/uart_hw/defs.asm
index 96ab2d0..1c4da51 100644
--- a/avr/modules/uart_hw/defs.asm
+++ b/avr/modules/uart_hw/defs.asm
@@ -42,8 +42,3 @@
 .equ UART_HW_IFACE_SIZE                = UART_HW_IFACE_OFFS_MSGIDBUF_DATA+UART_HW_IFACE_MSGIDBUF_SIZE
 
 
-.equ UART_HW_IFACE_FN_ISR_CHECKATTN    = 0
-.equ UART_HW_IFACE_FN_ISR_READCHAR     = 1
-.equ UART_HW_IFACE_FN_ISR_WRITECHAR    = 2
-.equ UART_HW_IFACE_FN_COUNT            = 3
-
diff --git a/avr/modules/uart_hw/lowlevel.asm b/avr/modules/uart_hw/lowlevel.asm
index ff2f527..cc6a902 100644
--- a/avr/modules/uart_hw/lowlevel.asm
+++ b/avr/modules/uart_hw/lowlevel.asm
@@ -43,27 +43,6 @@ UART_HW_InitInterface:
 
 
 
-; ---------------------------------------------------------------------------
-; @routine UART_HW_JumpToFunction @global
-;
-; @param R16 function number (see @ref UART_HW_IFACE_FN_ISR_CHECKATTN)
-; @param Y pointer to interface data in SRAM (see @ref UART_HW_IFACE_OFFS_STATE)
-; @param Z pointer to IFACE jump table for the given interface
-; @clobbers R16, R17, X
-
-UART_HW_JumpToFunction:
-  cpi r16, UART_HW_IFACE_FN_COUNT
-  brcc UART_HW_JumpToFunction_ret ; return with cleared CFLAG
-  mov xl, zl
-  mov xh, zh
-  add xl, r16
-  adc xh, xl
-  sub xh, xl
-  push xl
-  push xh
-UART_HW_JumpToFunction_ret:
-  ret ; indirect jump to address we just pushed onto the stack or return on error
-; @end