Raj Shetgar wrote:
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Venkat Ramu wrote:
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Hi Raj

can u post me the ckt, is it as simple as I2C like no additional hardware only 2 or more pins pulled out for connection to the reader

Venkat

Its much simpler than the IIC,it has what is called as DATA0 and DATA1, All I used to decode the data is this document ->http://www.pyramidseries.com/tech-docs...cument.pdf

Its too simple, You can finish this within a day.



;ports
DH bit p3.2 ;int0
DL bit p3.3 ;int1


;bits
rfid_sense bit 0x00
rfid_flag_full bit 0x01
DH_DL_bit bit 0x02

;variables
rfid_ptr equ 0x30
rfid_bank equ 0x31;0x32,0x33,0x34(total 4 ram locations)
buffer equ 0x34
pulse_cnt0 equ 0x35
pulse_cnt1 equ 0x36


org 0000
ljmp on_rst



org 0003h ;int0 isr
setb rfid_sense
reti

org 000bh ;timer0 isr
lcall isr_t0
reti

org 0013h ;int1 isr
setb rfid_sense
reti


org 0050h
on_rst:
lcall all_init

main_loop:
jb rfid_sense,collect_rfid
jb rfid_flag_full,parse_rfid
sjmp main_loop



;####################################################################################
collect_rfid:
clr ea ;diasable all ints(global enable bit)
clr ex0 ;disable int0
clr ex1 ;disable int1
jnb DH,$ ;wait till it comes back to high,igonre first bit(parity bit)
jnb DL,$ ;wait till it comes back to high,igonre first bit(parity bit)
lcall rfid_loop ;go collect the remaining bits
clr rfid_sense ;clear the flag
ljmp main_loop ;go back to the main loop

rfid_loop:
jnb DH,update_rfid_DH
jnb DL,update_rfid_DL
jnb rfid_flag_full,rfid_loop ;keep looping till all the 24 bits are collected(2 bist are ignored ->parity bits)
ret

update_rfid_DH:
setb ea ;interrupt golbal enable bit,enable timer0 int
clr tr0 ;stop timer0 for reload
mov th0,#00 ;reload the timer0
mov tl0,#00 ;reload the timer0
setb tr0 ;start the timer0 for 65 milli sec
jnb DH,$ ;wait till the DH goes back to high state
setb DH_DL_bit ;
sjmp backup_rfid ;store the received bit

update_rfid_DL:
setb ea ;interrupt golbal enable bit,enable timer0 int
clr tr0 ;stop timer0 for reload
mov th0,#00 ;reload the timer0
mov tl0,#00 ;reload the timer0
setb tr0 ;start the timer0 for 65 milli sec
jnb DL,$ ;wait till the DH goes back to high state
clr DH_DL_bit ;
sjmp backup_rfid ;store the received bit

backup_rfid:
inc pulse_cnt0
inc pulse_cnt1
mov a,buffer
mov c,DH_DL_bit
rrc a
mov buffer,a
mov a,pulse_cnt0
cjne a,#8,chk1
mov r0,rfid_ptr
mov @r0,buffer
inc r0
mov rfid_ptr,r0
mov buffer,#00
mov pulse_cnt0,#00
chk1:
mov a,pulse_cnt1
cjne a,#24,backup_rfid_exit
setb rfid_flag_full ;all the bits have arrived
clr ea ;disable all int's
clr tr0 ;stop timer0
mov pulse_cnt0,#00
mov pulse_cnt1,#00
backup_rfid_exit:
sjmp rfid_loop


;####################################################################################

;####################################################################################
parse_rfid:

mov rfid_ptr,#rfid_bank ;get the base arrds of the rfid bytes(26 bits,4 bytes)
mov r0,rfid_ptr
mov a,@r0
inc r0
mov rfid_ptr,r0
lcall convert;arugument in acc

mov sbuf,r0 ;first send the facility code
jnb ti,$
clr ti


mov sbuf,r1
jnb ti,$
clr ti

mov sbuf,r2
jnb ti,$
clr ti



mov sbuf,#',' ;delimiter
jnb ti,$
clr ti


mov r0,rfid_ptr
mov a,@r0
inc r0
mov rfid_ptr,r0
lcall convert

mov sbuf,r0 ;send the higher part of the 16 bit card id
jnb ti,$
clr ti


mov sbuf,r1
jnb ti,$
clr ti


mov sbuf,r2
jnb ti,$
clr ti


mov r0,rfid_ptr
mov a,@r0
inc r0
mov rfid_ptr,r0
lcall convert



mov sbuf,r0 ;send the lower part of the 16 bit card id
jnb ti,$
clr ti


mov sbuf,r1
jnb ti,$
clr ti



mov sbuf,r2
jnb ti,$
clr ti



mov sbuf,#13 ;carriage return
jnb ti,$
clr ti
mov sbuf,#10 ;line feed
jnb ti,$
clr ti



clr rfid_flag_full ;clear to indicate that the 26 bits are parsed

mov ie,#1000$0101b ;int0 and int1 enabled

ljmp main_loop
;####################################################################################

;####################################################################################
all_init:
mov ie,#1000$0101b ;int0 and int1 enabled
setb tcon.0 ;make int0 edge triggerd
setb tcon.2 ;make int1 edge triggered

clr rfid_sense ;flag to indicate start of the 26 bits
clr rfid_flag_full ;flag to indicate all 26 bits have arrived
clr DH_DL_bit
mov buffer,#00 ;ponter to point one location in the 4 bytes
mov rfid_ptr,#rfid_bank;4 memory locations to hold 26 bits
mov pulse_cnt0,#00
mov pulse_cnt1,#00

;timer0 intialise used to generate 65 milli sec
mov tmod,#01h ;timer0 in mode1(16 bit timer)
mov th0,#00
mov tl0,#00
;serial intialise for 9600 baud
MOV TMOD,#21H ;TIMER 1 , MODE 2(AUTO RELOAD) and timer0 in mode 1(16 bit timer)
MOV TH1,#0FDH ;9600 BAUD RATE
MOV SCON,#50H ;8 BIT,1 STOP, REN ENABLE
SETB TR1 ;START TIMER 1

ret

;####################################################################################

;####################################################################################
isr_t0:
clr tr0
mov th0,#00
mov tl0,#00

clr ti
mov sbuf,#'T'
jnb ti,$
clr ti


clr rfid_sense ;flag to indicate start of the 26 bits
clr rfid_flag_full ;flag to indicate all 26 bits have arrived
clr DH_DL_bit
mov buffer,#00 ;ponter to point one location in the 4 bytes
mov rfid_ptr,#rfid_bank;4 memory locations to hold 26 bits
mov pulse_cnt0,#00
mov pulse_cnt1,#00

mov ie,#1000$0101b ;int0 and int1 enabled
ret
;####################################################################################


;@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
;THIS WILL CONVER THE BINARY NUMBER IN ACCUMULATOR INTO ASCII
;ARGUMENT1 --> ACCUMULATOR ==>THE NUMBER TO BE CONVERTED
;RETURN --> R2 ==> UNITS PLACE
; --> R1 ==> TENTS PLACE
; --> R0 ==> HUNDREDS PLACE

CONVERT:
MOV B,#10
DIV AB
MOV R2,B

MOV B,#10
DIV AB
MOV R1,B

MOV R0,A

MOV A,#30H ;CONVERT THE BCD INTO ASCII
ORL A,R2
MOV R2,A ;R2 ==> UNITS PLACE

MOV A,#30H ;CONVERT THE BCD INTO ASCII
ORL A,R1
MOV R1,A ;R1 ==> TENTS PLACE

MOV A,#30H ;CONVERT THE BCD INTO ASCII
ORL A,R0
MOV R0,A ;R0 ==> HUNDREDS PLACE

RET
;@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
end





Regards
Raj Shetgar

to Raj:
hi,wiegand26 only has 26bits data,why check CR?
and if i use check-method instead of interrupt and a hareware watchdog is on-board,how to write program?thanks!