C8051F020 DAC

See chapter 8 of C8051F02x.pdf

• The C8051F020 contains two 12-bit DAC’s

• Output swing from 0V to VREF-1LSB

• Several possible sources for VREF

• Internal reference = 1.2 X 2 = 2.4 volts, AV+, external.

• Possible update sources:

• Update on write to high byte of DAC. (Default)

• Update on timer overflow.

• Position of 12 bits used can be varied.

0 0 1 1 1

MOV REF0CN,#07H ;USE INTERNAL VREF

1 0 0 0 0 0MOV DAC0CN,#10000000B ;EN DAC0, UPDATE ON WR, LEFT JUSTIFIED

INIT_DACS: MOV REF0CN,#07H ;USE INTERNAL VREF MOV DAC0CN,#10000000B ;EN DAC0, UPDATE ON WR, LEFT JUSTIFIED MOV DAC1CN,#10000000B ;EN DAC1, UPDATE ON WR, LEFT JUSTIFIED RET

WR_DAC0: MOV DAC0L,R7 ;OUTPUT LOW BYTE MOV DAC0H,R6 ;OUTPUT HIGH BYTE RET

WR_DAC1: MOV DAC1L,R7 ;OUTPUT LOW BYTE MOV DAC1H,R6 ;OUTPUT HIGH BYTE RET

MOV XBR0,#00000100B ;UART 0 TX TO P0.0, RX TO P0.1

MOV XBR1,#10000000B ;SYSCLK OUT

MOV XBR2,#01000000B ;ENABLE THE CROSSBAR