CHAPTER 3 METHODOLOGY 3.1 Overview The Water Monitoring ...

ADC0802, ADC0803, ADC0804IRQ (4)† [D]††10KR/W (34) [6]ADC0802 - ADC080412CSRDV+CLK R20193 WR DB 0 18LSB+10µFD 0 (33) [31]5V (8)A B C1 2 3RDIORQWR74C32RDWR23ADC0802-ADC0804ANALOGINPUTS150pF4 CLK IN5 INTR6 V IN (+)7 V IN (-)8 AGND9 V REF /210 DGND6DB 1 17DB 2 16DB 3 15DB 4 14DB 5 13DB 6 12DB 7 111231 4/2 DM80925MSBD 1 (32) [29]D 2 (31) [K]D 3 (30) [H]D 4 (29) [32]D 5 (28) [30]D 6 (27) [L]D 7 (26) [J]A 12 (22) [34]A 13 (23) [N]A 14 (24) [M]A 15 (25) [33]VMA (5) [F]† Numbers in parentheses refer to MC6800 CPU Pinout.†† Numbers or letters in brackets refer to standard MC6800 System Common Bus Code.FIGURE 22. MAPPING THE A/D AS ANI/O DEVICE FOR USEWITH THE Z-80 CPUFIGURE 23. ADC0802 TO MC6800 CPU INTERFACE10K1819CB 1CB 2ANALOGINPUTS150pFADC0802 - ADC080412CSRDV+CLK R2019345WRCLK ININTRDB 0 18DB 1 17DB 2 166 V IN (+) DB 3 157 V IN (-) DB 4 148 AGND DB 5 139 V REF /2 DB 6 1210 DGND DB 7 11LSBMSB5V1011121314151617MC6820(MCS6520)PIAPB 0PB 1PB 2PB 3PB 4PB 5PB 6PB 7FIGURE 24. ADC0802 TO MC6820 PIA INTERFACE6-19