RPC-UHF RADIOMETRIX [Radiometrix Ltd], RPC-UHF Datasheet - Page 23

• Manufacturer Part Number: RPC-UHF
• Description: Radio Packet Controller
• Manufacturer: RADIOMETRIX [Radiometrix Ltd]

;SUBROUTINE OUT_BYTE
;OUT_BYTE
;
;
;
;
;
;
;
;
;
OUT_BYTE
;
;
WACCEPT
;
;WE GOT ACCEPTANCE SO IT'S OK TO DRIVE BUS
;
;
WDUN
;
;LS NIBBLE OF (FSR) IS SENT , NOW DO MS NIBBLE
;
;
;
WACCEPT1
;
;
WDUN1
;
;
;
;--------------------------------------------------------------------
; SUBROUTINE - LISTEN_BUS , SET DATA BUS TO INPUT
;
LISTEN_BUS
;
;--------------------------------------------------------------------
Radiometrix Ltd, RPC
WRITE A BYTE FROM FILE POINTED TO BY FSR TO RPC
W IS DESTROYED
NOTE
WARNING
DETECTING A TXA FROM THE RPC.
(i.e. call LISTENBUS)
SWAPF INDF,W
ANDLW B'11110000' ;JUST THE NIBBLE
IORLW B'00000010' ;SET TXR LOW, LEAVE RXA HIGH
MOVWF RPC
BTFSC RPC,TXA
GOTO
BSF
MOVLW B'00001001' ;DRIVE BUS
MOVWF RPC_DDR
BCF
BSF
BTFSS RPC,TXA
GOTO
MOVF
ANDLW B'11110000' ;JUST THE MS NIBBLE
IORLW B'00000010' ;SET TXR LOW (BIT 2), RXA STAYS HIGH
MOVWF RPC
BTFSC RPC,TXA
GOTO
BSF
BTFSS RPC,TXA
GOTO
RETURN
BSF STATUS,RP0
MOVLW B'11111001' ;BUS TO INPUT
MOVWF RPC_DDR
BCF
RETURN
BYTE IS SENT TO RPC
BUS IS LISTENING TO RPC
THIS ROUTINE WILL HANG THE HOST UNTIL THE RPC
ACCEPTS THE TRANSFER OF TWO NIBBLES
WACCEPT
STATUS,RP0
STATUS,RP0
RPC,TXR
WDUN
INDF,W
WACCEPT1
RPC,TXR
WDUN1
STATUS,RP0
OUT_BYTE WILL SET THE DATA BUS TO DRIVE AFTER ;
THE CALLING ROUTINE MUST SET 4 DATA LINES
BACK TO I/P ON COMPLETION OF PACKET TRANSFER ;
;GET LS NIBBLE FROM FILE (VIA FSR) INTO
;BITS 4 to 7 of W
;SET TXR LOW, OUTPUT NIBBLE
;WE GOT A TX ACCEPT BACK YET?
;NO, SO LOOP BACK AND WAIT
;SELECT PAGE 1
;SELECT PAGE 0 BUS IS NOW DRIVING
;REMOVE REQUEST, DATA IS ON BUS
;HAS DATA BEEN READ?
;WAIT TILL RPC REMOVES ACCEPT
;GET MS NIBBLE FROM FILE (VIA FSR)
;OUTPUT NIBBLE + TXR LOW
;WE GOT A TX ACCEPT BACK YET?
;NO, SO LOOP BACK AND WAIT
;REMOVE REQUEST, DATA IS ON BUS
;HAS DATA BEEN READ?
;WAIT TILL RPC REMOVES ACCEPT
;SELECT PAGE 1
;SELECT PAGE 0
page 23