Low-Power, 8-Channel,

Serial 10-Bit ADC

22

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LDD

#$0800

STD

SPCR2

;set ENDQP to $8 for 9 transfers

***** Initialize QSPI Command RAM *****

LDAA

#$80

;CONT=1,BITSE=0,DT=0,DSCK=0,PCS0=ACTIVE

STAA

$FD40

;store first byte in COMMAND RAM

LDAA

#$C0

;CONT=1,BITSE=1,DT=0,DSCK=0,PCS0=ACTIVE

STAA

$FD41

STAA

$FD42

STAA

$FD43

STAA

$FD44

STAA

$FD45

STAA

$FD46

STAA

$FD47

LDAA

#$40

;CONT=0,BITSE=1,DT=0,DSCK=0,PCS0=ACTIVE

STAA

$FD48

***** Initialize QSPI Transmit RAM *****

LDD

#$008F

STD

$FD20

LDD

#$00CF

STD

$FD22

LDD

#$009F

STD

$FD24

LDD

#$00DF

STD

$FD26

LDD

#$00AF

STD

$FD28

LDD

#$00EF

STD

$FD2A

LDD

#$00BF

STD

$FD2C

LDD

#$00FF

STD

$FD2E

LDD

#$0000

STD

$FD30

PULB

PULA

RTS

READ192:

;This routine triggers the QSPI microsequencer to autonomously

;trigger conversions on all 8 channels of the MAX192. Each

;conversion result is stored in the receive data RAM.

PSHA

LDAA

#$80

ORAA

SPCR1

STAA

SPCR1

;just set SPE

PULA

RTS

***** Interrupts/Exceptions *****

BDM: BGND

;exception vectors point here

;and put the user in background debug mode

Figure 20. MAX192 Assembly-Code Listing (continued)