Microprocessors Interfacing

1. In the 1ivgre helum: a Mrisfy tur adlrowes if the ingut ant the estyed pons b. Is the interficed thenksy we 10 mape? - Pre A as m expea poer is Mhode ol b. Pat 0ax as iatsue pat in Mede 1 far interuet 10 c. Pare Ce as an autpat pour is Mtede 0. the die mbeneter aleren ia Tigae 3.9. 1 The sores and 8244 nin at 8 MIIt asl 2 Mile nopoutholy. 1. In the Figure below: a. Identify the addresses of the input and the output ports. b. Is the interfaced memory or I/O maps? c. Write instructions to read the input port and continue to read it until both switches close (by the operator). When both switches are closed, turn on all the LEDs. +5V 2. Write initialization instructions for the 8255A to set up a. Port A as an output port in Mode 0 . b. Port B as an output port in Mode 1 for interrupt I/O. c. Port Cu as an output port in Mode 0 . Use the schematic shown in Figure 3.9. 3. Figure below shows the 8086 microprocessor interfaced to the 8254 programmable timer. The 8086 and 8254 run at 8MHz and 2MHz respectively. a. Identify the port addresses of the control register and 3 counters. b. Write a program to generate a 1KHz square wave from Counter 0 . c. Write a program to interrupt the microprocessor after 10ms from Counter 1