habe den code mal in Bascom geladen.
Code:
$regfile = "m32def.dat"
$framesize = 32
$swstack = 32
$hwstack = 32
$crystal = 16000000
$baud = 9600

'http://de.wikipedia.org/wiki/Wochentagsberechnung#Schaltjahreskorrektur
   'Days = Makedec(days)
   'Months = Makedec(months)
   'Years = Makedec(years)
   Weekdays = Days Mod 7
   J = Months - 1
   J = Lookup(j , Monat)
   Weekdays = Weekdays + J
   J = Years \ 4
   J = J + Years
   J = J Mod 7
   Weekdays = Weekdays + J
   Weekdays = Weekdays + 6                                  'Jahrhunderziffer
   I = Years Mod 4 : If I = 0 Then If Years <> 0 Then J = 6 Else J = 0
   Weekdays = Weekdays + J
   Weekdays = Weekdays Mod 7
   'Days = Makebcd(days)
   'Months = Makebcd(months)
   'Years = Makebcd(years)
   Lcd_textbuffer1 = Lookupstr(weekdays , Weekday)
   'Locate 3 , 5 : Lcd Lcd_textbuffer1
   Lcd_text = Lcd_textbuffer1 : Call Lcd_print(5 , 3 , Lcd_text)
Return

Monat:
Data 0 , 3 , 3 , 6 , 1 , 4 , 6 , 2 , 5 , 0 , 3 , 5

Weekday:
Data "So" , "Mo" , "Di" , "Mi" , "Do" , "Fr" , "Sa"
bekomme aber immer error 46 in linie 12 und 13.