I fear I've damaged the LS6203 chip. I was just setting up to test the motor control when I found that the 9V battery, and the LS6203 were hot
I'd hooked the battery up the wrong way round.
Once everything had cooled off, I tried with the correct connections. No joy. No motor movement: 0V measured across MotA/MotB while the motors test program was running.
To test GPIO18, I hooked up GP18-B7, and put in the jumper B7 : then running the leds test program showed D7 would light up, and running the motors test program also lights up D7 with a variable brightness.
Fuse is OK, R23 seems to test as 0.5ohm(?)
Will I need to replace the LS6203?