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8255 PIA

When the PIA is inserted in the board ..current  consumption is ~105mA.

To test the chip operation..look up specks on 8255 ..There should be tons on the internet ...  Intel 8255

In this case we can test the port A of the PIA via fBASIC.

Port addresses are: control register C803, Port A ..C800

So what is needed is to set port A ..say to output and all other ports to input

From 8255 data that would make the byte to control register --> #8B  (hex)  ... and if we send  say ... #F0 to address #c800 .. that would turn top 4 bits on and other 4 low bits off on port A.
Below is example of the commands in fBasic to do that.. To test the port output use a logic probe of some sort ..or even a voltmeter .. Whalla!!