diff --git a/avr/devices/all/hw_tn841.asm b/avr/devices/all/hw_tn841.asm
index 1804319..9f2924b 100644
--- a/avr/devices/all/hw_tn841.asm
+++ b/avr/devices/all/hw_tn841.asm
@@ -19,14 +19,14 @@
 
 systemInitHardware:
   ; set all ports as inputs and enable internal pull-up resistors
-  ldi r16, 0xff
+;  ldi r16, 0xff
   clr r17
 
-  out DDRA, r17  ; all input
-  sts PUEA, r16  ; enable pull-up on all
+  outr DDRA, r17  ; all input
+  outr PUEA, r17  ; disable pull-up on all
 
-  out DDRB, r17  ; all input
-  sts PUEB, r16  ; enable pull-up on all
+  outr DDRB, r17  ; all input
+  outr PUEB, r17  ; disable pull-up on all
 
   ret
 ; @end
@@ -50,6 +50,22 @@ systemSetSpeed:
   clr r16           ; SUT=0, CLKPS=0
   sts CCP, r17
   sts CLKPR, r16
+
+#if 0
+  ; read and set calibration data
+  push r15
+    inr r15, SREG
+    cli
+    ldi zl, 0
+    ldi zh, 1
+    ldi r16, (1<<RSIG) | (1<<SPMEN)
+    outr SPMCSR, r16
+    lpm r17, Z
+    outr OSCCAL0, r17
+    outr SREG, r15
+  pop r15
+#endif
+
 .endif
 
   ret
@@ -118,16 +134,16 @@ systemSetupTimer0:                            ; setup timer for IRQ every 100ms
 
   ldi r16, (1<<OCF0A)             ; clear pending interrupts
 .ifdef TIFR0
-  out TIFR0, r16
+  outr TIFR0, r16
 .else
-  out TIFR, r16
+  outr TIFR, r16
 .endif
   
   ldi r16, (1<<OCIE0A)            ; Timer/Counter0 Output Compare Match A Interrupt Enable
 .ifdef TIMSK0
-  out TIMSK0, r16
+  outr TIMSK0, r16
 .else
-  out TIMSK, r16
+  outr TIMSK, r16
 .endif
   sec
   ret