Hello everybody!
I have a question about interrupt routine. I have been using two interrupts in my program, external int.1 & 2. Inputs are conected to the same signal int1-direct,int0-via inverter. So, at the beginning of the program I set:

;timer 0 is in timer mode,software controll
MAIN:
CLR after_ex0
CLR after_ex1
SETB EX1 ;external int.1 enable
CLR EX0 ;external int.0 disable
SET EA ;global interrupt enable
JNB after_ex1,$ ;wait for int.1 service routine end
JNB after_ex0,$ ;wait for int.0 service routine end
CALL display_results

and my program is waiting for 1 to 0 transistion on INT1. Interrupt 1 service routine is setting only four bits (so as int.0):

IRQEX1:
SETB TR0 ;starts timer 0
CLR EX1 ;int.1 disable
SET EX0 ;int.0 enable
SET after_ex1
RETI

IRQEX0:
CLR TR0 ;stops timer 0
CLR EX0 ;int.0 disable
SET after_ex0
RETI

My questions is: can I clear EX1 bit during interrupt service routine?
Program should measure the low pulse using timer 0. The results of measuring are so amazing - I calculate the input pulse and its duration would be about 380 machine cycles, but the results of measuring is... 12.
I have made changes and now, my program looks like below:

MAIN:
CLR after_ex0
CLR after_ex1
SETB EX1 ;int.1 enable
CLR EX0 ;int.0 disable
SET EA
JNB after_ex1,$
CLR EX1 ;int.1 disable
SETB EX0 ;int.0 enable
JNB after_ex0,$
CLR EX0 ;int.0 disable
CALL display_results


IRQEX1:
SETB TR0 ;starts timer 0
SET after_ex1
RETI

IRQEX0:
CLR TR0 ;stops timer 0
SET after_ex0
RETI

And the results are diffrent (about 30 times!!!). Why?
I can evaluate the problem myself, but at this moment I haven\'t my ICE. Could anybody answer my question?