My first use of Microchip Studio 7 to ATtiny13A. - My first use of an AVR actually.
I have AVR on circuit board. I can program the AVR with the 6 wire (MOSI, MISO, SCK etc) . The problem I have is when certain components are connected, I get a failed to launch program just after the compiler output:
========== Build: 1 succeeded or up-to-date, 0 failed, 0 skipped ==========
I think I get a time out error during the ‘Loading Executable (14%)’ stage.
I can solve this by disconnecting the link to the servo’s MOSFET driver but this will be inconvenient when I move the build to a finished unit. I’d still like to be able to program the AVR ‘in situ’ as there are some ‘select on test’ parameters that will need changing.
I can understand that connecting a 15mA load to a MISO pin or the output from a voltage difference amplifier (I tried these) would impact on the programming signals (I’ve moved these away to PINB3 and PINB4).
I have to use PINB1 for the servo as I want to use the PWM on OC0B (MISO).
I have a 10M resistor from PINB1 to Vcc and a 10K resistor from PINB1 to the input gate of my MOSFET.
I’ve tried increasing the 10K resistor to 100K but that still seems to have an adverse impact on the programming communication. If I increase it further to 1M, the MOSFET does not switch on to drive the servo.
Could anyone aim me at a spec sheet that defines what I may and may not connect to the MOSI / MISO etc pins in parallel with the Pololu so I can design a circuit that will allow ‘in situ’ programming.
It’s not a big issue but one I’d like to understand so I may avoid in the final build.
I have tried a 10uF cap across the AVR pcb supply rails. Am I missing some capacitors on the data pins?