I'm working through AN3905 on an M52223EVB and running into a strange problem - when I try to execute the
"output_port = fopen("gpio:write", (char_ptr) &output_set);"
statement in ioDrivers.c, it returns output_port as NULL (0).
I have copied the code exactly as is shown in AN3905 pages 18-19 *Appendix C ioDriver.c Module for M52259DEMO_MQX_RTOS Project" after reviewing the GPIO pin addresses between the '52259 and '52223 User Guides (and finding them to seem to be identical).
Looking at the actual addresses for the bits generated in "output_set" (ie 0x80000038 for LED_1), I'm not 100% sure if they're right.
When adding the ioDrivers.c (and "tasks.c"), I used the CW10 "New" and "C Source File" option and then entered the code in here - I could not find an option to specify that the code executes in a supervisor mode.
Can anybody comment? The software is CW10 and MQX 3.6.