diff --git a/forth.asm b/forth.asm
index bc39be3..1a9ae9d 100644
--- a/forth.asm
+++ b/forth.asm
@@ -530,8 +530,8 @@ COLD:
         .endif
         MOV     BG_TIM_PSCR,#3  ; prescaler 1/(2^3) = 1/8
         .endif
-        LDW     X,#BG_TIM_REL   ; "BGTIMREL" timer reload for BG task
-        LDW     BG_TIM_ARRH,X   ; timer not yet started - use 16bit transfer
+        MOV     BG_TIM_ARRH,#(BG_TIM_REL/256)  ; reload H
+        MOV     BG_TIM_ARRL,#(BG_TIM_REL%256)  ;        L
         MOV     BG_TIM_CR1,#0x01 ; enable background timer
         MOV     BG_TIM_IER,#0x01 ; enable background timer interrupt
         .endif
diff --git a/inc/defconf.inc b/inc/defconf.inc
index b0c09bc..b828be4 100644
--- a/inc/defconf.inc
+++ b/inc/defconf.inc
@@ -3,7 +3,7 @@
 ;       Default settings for all kinds of options
 ;--------------------------------------------------------
         RELVER1          = 2    ; Revision digit 1
-        RELVER0          = 4    ; Revision digit 0
+        RELVER0          = 5    ; Revision digit 0
 
         TERM_LINUX       = 1    ; LF terminates line
 
diff --git a/lib/INTRX b/lib/INTRX
new file mode 100644
index 0000000..689f214
--- /dev/null
+++ b/lib/INTRX
@@ -0,0 +1,92 @@
+\ STM8 eForth buffered UART receive
+\ refer to github.com/TG9541/stm8ef/blob/master/LICENSE.md
+
+\ The code assumes target CPU resource definitions and that
+\ RX buffer length are  defined prior to loading!
+\ More in the example at the end of the file
+
+#require WIPE
+#require :NVM
+#require ALIAS
+#require ]B!
+#require '?KEY
+
+5 CONSTANT #RIEN
+
+NVM
+  VARIABLE rxbuf RBLEN 2- ALLOT
+  VARIABLE rxp       \ UART RX ISR buffer write pointer
+  VARIABLE rrp       \ ?RXB buffer read pointer
+
+  \ increment buffer pointer w/ wrap around
+  :NVM ( a -- )
+    DUP @ 1+ ( a ab1 ) [ rxbuf RBLEN + 1- ] LITERAL OVER < IF
+      ( a n1 ) DROP rxbuf ( a n0 )
+    THEN
+    ( a n ) SWAP !
+  ;RAM ALIAS rpi
+
+  \ RX ISR handler
+  :NVM
+    SAVEC
+    UART1_DR C@ rxp @ C! rxp rpi
+    IRET
+  [ OVERT INT_UARTRX !
+
+  \ like ?RX only buffered
+  : ?RXB ( -- c T | F )
+    rrp @ rxp @ = IF
+      0
+    ELSE
+      rrp @ C@ -1 rrp rpi
+    THEN
+  ;
+
+  \ Interrupt RX UART handler
+  : INTRX ( -- )
+    [ ' ?RXB ] LITERAL '?KEY !
+    rxbuf DUP rxp ! rrp !
+    [ 1 UART1_CR2 #RIEN ]B!
+  ;
+
+WIPE RAM
+
+\\ Example
+
+\ select the generic STM8S controller first
+
+\ alternatively specify STM8S103, STM8S105 or STM8S207
+\res MCU: STM8S103
+
+\ load (or define) device independent constants
+\res export INT_UARTRX UART_DR UART_CR2
+
+\ define the UART buffer length
+8 CONSTANT RBLEN
+
+\ then load the controller independent code
+#require INTRX
+
+\ put it to work
+#require WIPE
+#require :NVM
+#require OSCFREQ
+#require UART_DIV
+#require UARTBRR
+
+NVM
+  'BOOT ( xt )
+  :NVM
+    INTRX
+    ( xt ) LITERAL EXECUTE
+  ;NVM 'BOOT !
+
+  \ calculate UART_DIV settings for 3840*10 = 38400 baud @ CPU clock rate
+  3840 OSCFREQ UART_DIV UARTBRR !
+WIPE RAM
+
+\ make it survive a RESET command
+#require PERSIST
+PERSIST
+
+\ remember to set your terminal program (e.g. e4thcom) to 38400 baud!