| ??? 10/13/08 11:52 Read: times |
#159017 - Multiple Problems Responding to: ???'s previous message |
Dear Ranjit,
A snipet of your posted code is as follows Ranjit Kumar Gupta said:
I want to initialise the interrupt timer but can't do the same with following code please help.
;testing timer ; ORG 0 CALL INTR jmp 40h ORG 0BH JMP IT1 org 40h MOV SP,#60H MOV @R1,#0 LOOP: SETB TR0 NOP JMP LOOP INTR: MOV SCON,#50H MOV TH0,#F4H MOV TL0,#F4H MOV TMOD,#20H SETB TR0 RET IT1: MOV A,@R1 ADD A,#1 DA A MOV @R1,A reti END Problem: 1. you are initialising SFR related to timer zero, but you are configuring timer1 in auto reload. (actually you need to configure timer0 in same) 2. R1 is not initialised (or is it assumed to have any value that is there on reset?) 3. at org 0 you have 2 instructions 1 call & 1 jmp. instead you can have only 1 jmp instruction as sjmp 40h & at org 40 you can call INTR 4. The most important is, when you intend to use interrupt you need to enable it. Your code should have one of the following to enable timer0 interrupt in INTR subroutine mov IE, #82h or setb ET0 followed with setb EA ( Also why are you initialising SCON registor ) please make all four changes, test them & reply Regards, Mahesh |
| Topic | Author | Date |
| Help need in Timer Interrupt | 01/01/70 00:00 | |
| which timer are you using ? | 01/01/70 00:00 | |
| Thanks Arun | 01/01/70 00:00 | |
| where do you set R1? | 01/01/70 00:00 | |
| Multiple Problems | 01/01/70 00:00 | |
Comments? | 01/01/70 00:00 |