![](http://datasheet.mmic.net.cn/280000/MPX2202GVP_datasheet_16098581/MPX2202GVP_377.png)
3–231
Motorola Sensor Device Data
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099A 3D 50 TST $50 if ( digit[0] == 0 ) /* leading zero suppression */
099C 26 04 BNE $09A2
099E 3F 02 CLR $02 portc = 0;
09A0 20 07 BRA $09A9 else
09A2 BE 50 LDX $50 portc = ( lcdtab[digit[0]] ); /* 100’s digit */
09A4 D6 08 00 LDA $0800,X
09A7 B7 02 STA $02
09A9 3D 50 TST $50 if ( digit[0] == 0 && digit[1] == 0 )
09AB 26 08 BNE $09B5
09AD 3D 51 TST $51
09AF 26 04 BNE $09B5
09B1 3F 01 CLR $01 portb=0;
09B3 20 07 BRA $09BC else
09B5 BE 51 LDX $51 portb = ( lcdtab[digit[1]] ); /* 10’s digit */
09B7 D6 08 00 LDA $0800,X
09BA B7 01 STA $01
09BC BE 52 LDX $52 porta = ( lcdtab[digit[2]]+1 ); /* 1’s digit + decimal point */
09BE D6 08 00 LDA $0800,X
09C1 4C INCA
09C2 B7 00 STA $00
09C4 9A CLI CLI;
09C5 CD 08 17 JSR $0817 delay();
09C8 81 RTS }
/****************************************************************/
void display_psi(void)
/* At power–up it is assumed that the pressure port of the sensor
is open to atmosphere. The code in initio() delays for the
sensor and power to stabilize. One hundred A/D conversions are
averaged and divided by 100. The result is called xdcr_offset.
This routine calls the A/D routine which performs one hundred
conversions, divides the result by 100 and returns the value.
If the value returned is less than or equal to the xdcr_offset,
the value of xdcr_offset is substituted. If the value returned
is greater than xdcr_offset, xdcr_offset is subtracted from the
returned value. That result is multiplied by a constant to yield
pressure in PSI * 10 to yield a ”decimal point”.
*/
{
while(1)
{
09C9 3F 59 CLR $59 slope = 64;
09CB A6 40 LDA #$40
09CD B7 5A STA $5A
09CF B6 03 LDA $03 k = portd & 0xc0; /* this lets us ”rubber” the slope to closer fit
09D1 A4 C0 AND #$C0
09D3 B7 62 STA $62
the slope of the sensor */
09D5 A1 80 CMP #$80 if ( k == 0x80 ) /* J2 removed, J1 installed */
09D7 26 06 BNE $09DF
09D9 3F 59 CLR $59 slope = 65;
09DB A6 41 LDA #$41
09DD B7 5A STA $5A
09DF B6 62 LDA $62 if ( k == 0x40 ) /* J1 removed, J2 installed */
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