Global variable in startup
unsigned mdriver_max;
The mdriver_max is a global variable in startup in the file mdriver_max.c. Since most of the time spent in startup is copying the OS image from flash to RAM, this value is the amount of data (in bytes) to copy between iterations of your minidriver handler function. You may need to modify this value based on the timing requirements of your driver.
The entry looks like:
unsigned mdriver_max = KILO(16);
QNX Neutrino