Help whit tmr1 on pic16f877a

[aratti]

I already tried tmr1 interrupt on overflow, as you are suggesting,

I suggested timer1 overflow with a true interrupt (Darrel Taylor interrupt) your code didn't use any interrupt.

You can try to use this simple snippet which uses the timer1 as a counter, without interrupt and works pretty well.

False           con 0
True            con 1
Z0               Var Byte
Cnts            var word
Tape_Len        Var Word

Logic_1         var portXx  ' any available free input

Motor = False
Brake = False
TMR1H = 0
TMR1L = 0

Main_Loop:
If ????? goto  Load_Tape
If ????? goto Set_Tape_L
goto Main_loop

Set_tape_L:
Tape_Len = XXXXX ' encoder pulses derived from the tape lenght desired
return

Start_Motor:
Brake = False
Motor = True
Return

Stop_Motor:
Motor = false
Brake = True
Pause 200
Brake = False
T1CON.0 = False
Return


Load_Tape:
 Cnts = 0
TMR1H = 0
TMR1L = 0
T1CON.0 = true
Resume_Halt:
Lcdout $FE, 1,   "  Press Yy to stop  "
Lcdout $FE, $C0, "--------------------"
Lcdout $FE, $94, "Now Loading Tape ..."
Lcdout $FE, $D4, "Loaded: ",dec Cnts

Gosub Start_Motor

For Z0 = 0 To 100                               ' 100 millisecs delay
pause 1
if Logic_1 = True then Hw_Halt                  ' check if emergency stop is activated
Next Z0

Winding:                                                ' loading start here
Cnts.highbyte = TMR1H
 Cnts.lowbyte = TMR1L
         If Cnts => Tape_Len then 
         gosub Stop_Motor                           ' if count = lenght desired stop motor
         goto Main_Loop
         End If
   if Logic_1 = True then Hw_Halt                ' If emergency stop key pressed stop motor

Lcdout $FE, $D4, "Loaded: ",dec Cnts            ' display updated count
goto Winding

Hw_Halt:
gosub Stop_Motor
Emergency_menu:
1) if ????? then goto Resume_Halt
2) if ????? then goto Main_Loop
goto Hw_Halt

End

Naturally you need to complete the code replacing the parts with ?????? and Xx with reference to your hardware setup.

Cheers

Al.