VIA TEST

Set port B of the VIA to output. Set port A of the VIA to input. Connect port B to port A on the VIA. (wire PB0 to PA0, PB1 to PA1, etc.). Now it's your turn to write some code. Modify a previous program to:

Initialize one port as input and one as output for the VIA.
Load a 00 into the accumulator
Store from the accumulator to "Port B" of VIA A000
Load to the accumulator from "Port A" of VIA A000
Store to TILs
Increment accumulator

Burn and test the program. If all is well the display will count as before. Disconnect the lowest line (PB0 - PA0) of the VIA and observe the count. The count should jump by two rather than by one as before. Show this to your lab instructor. This is the only time you will do this test. Due to the hardwire aspect of the test, you will not perform it on your Vector Board computer. You can though use the proto-board computer to test the VIA that will be used on the Vector Board.