PWM in 8051 with PCA counter

I read in documentation of AT89C51RC2, that I can make one of 5 ports to generate PWM signal if I set properly some registers. Some things I don’t understand. I don’t know what PCA counter is and how it behaves. There is what I came up with according to documentation.

CEX0 equ P1.3                   
CCAPM0 equ 0DAh                 
CCAP0L equ 0EAh                 
CCAP0H equ 0FAh
CL equ 0E9h
CCON equ 0D8h


DSEG at 30h   

CSEG                

    ORG 0000h               
    AJMP START

START:  
    MOV CCAPM0,#10000010B
    MOV CCAP0H,#0FFh
    MOV CCAP0L,#0FFh
    ORL CCON,#01000000B

MAIN:  

    MOV R6,#0FFh        
    DJNZ R6,$   

    MOV A,01000000B
    XRL A,CCON
    JNZ null 

 LJMP MAIN          

 null:
    MOV CL,#0
    MOV CCON,#01000000B
    LJMP MAIN 

END       

I don’t know which direction the CPA counter counts, whether it is needed to reset it, I don’t know If I forgot to set some registers. This code doesn’t work. Looks like the counter doesn’t even count.

Any suggestions?