Intel 8253 - Page 274

Functional Description (Continued)
Note 22: In order for the microprocessor to service subroutines and interrupts, the stack pointer must be dimensioned in the user’s program.
SAMPLE PROGRAM FOR Figure 15 ADC0801-MC6800 CPU INTERFACE
DS005671-A1
DS005671-25
FIGURE 16. ADC0801–MC6820 PIA Interface
ADC0801/ADC0802/ADC0803/ADC0804/ADC0805
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