Data Sheet

HX711

AVIA SEMICONDUCTOR

Reference Driver (Assembly)

/*-------------------------------------------------------------------

Call from ASM: LCALL ReaAD

Call from C: extern unsigned long ReadAD(void);

unsigned long data;

data=ReadAD();

----------------------------------------------------------------------*/

PUBLIC ReadAD

HX711ROM segment code

rseg HX711ROM

sbit ADDO = P1.5;

sbit ADSK = P0.0;

/*--------------------------------------------------

OUT: R4, R5, R6, R7 R7=>LSB

---------------------------------------------------*/

ReadAD:

CLR ADSK //AD Enable（PD_SCK set low）

SETB ADDO //Enable 51CPU I/0

JB ADDO,$ //AD conversion completed?

MOV R4,#24

ShiftOut:

SETB ADSK //PD_SCK set high（positive pulse）

NOP

CLR ADSK //PD_SCK set low

MOV C,ADDO //read on bit

XCH A,R7 //move data

RLC A

XCH A,R7

XCH A,R6

RLC A

XCH A,R6

XCH A,R5

RLC A

XCH A,R5

DJNZ R4,ShiftOut //moved 24BIT?

SETB ADSK

NOP

CLR ADSK

RET

END