ADC0801 National Semiconductor, ADC0801 Datasheet - Page 37

• Manufacturer Part Number: ADC0801
• Description: 8 BIT UP COMPATIBLE A/D CONVERTERS
• Manufacturer: National Semiconductor

Functional Description
Note 29: All numerical values are hexadecimal representations.
5.3 Multiple A/D Converters in a Z-80 Interrupt Driven
Mode (Continued)
The following notes apply:
• It is assumed that the CPU automatically performs a RST
• The address bus from the Z-80 and the data bus to the
• A/D data and identifying words will be stored in sequen-
7 instruction when a valid interrupt is acknowledged
(CPU is in interrupt mode 1). Hence, the subroutine start-
ing address of X0038.
Z-80 are assumed to be inverted by bus drivers.
tial memory locations starting at the arbitrarily chosen ad-
dress X 3E00.
FIGURE 21. Software for Auto-Zeroed Differential A/D
(Continued)
37
• The stack pointer must be dimensioned in the main pro-
• The peripherals of concern are mapped into I/O space
gram as the RST 7 instruction automatically pushes the
PC onto the stack and the subroutine uses an additional
6 stack addresses.
with the following port assignments:
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