tachometer lcd circuit

[Ricardoco]

Well ive been reading through the posts in this area and lots of people ask for a rev counter (Tachometer) but i cant seem to find any full examples, so i decided to go through all my zip files and shure enough. EPE did one a long time ago so long in fact that the back issue is no longer available. so firstly here is the code...

DEVICE 16F84 
DECLARE    XTAL 4 
DECLARE    LCD_TYPE 0 
DECLARE    LCD_DTPIN PORTB.4 
DECLARE     LCD_ENPIN PORTB.3 
DECLARE     LCD_RSPIN PORTB.2 
DECLARE    LCD_INTERFACE 4 
DECLARE     LCD_LINES 1 
PRINT $FE,128 
W0      VAR     WORD 

START:    
   COUNT porta.0,1000,W0     ' COUNT FOR 1 SEC 
   W0=(W0*10)/2 
   CLS 
   PRINT DEC W0*6," RPM  " 
   GOTO START

i know this if for a very old chip but that could be easily changed and below is the diagram, please be advised i have not tested this but as i said it is a nice place to start, and im sure if it has any mistakes the members will spot them, and make corrections as necessary.