Follow along as we build our own QNX image from absolute scratch, and learn about kernels, IPC, processes, file systems, and more along the way!
QNX From The Board Up Series
Explore how QNX masters the specialized I/O address space, using secure I/O Privilege Levels and dedicated instructions to communicate with peripherals while protecting system memory.
QNX From The Board Up Series
Dive into more internals of mmap() to understand files in memory, the semantics of MAP_PRIVATE vs. MAP_SHARED, and how these flags impact memory sharing and efficiency in QNX.
QNX From The Board Up Series
Take a quick break from memory to implement some common utilities like ls, shutdown, and uname on your own custom image. Simple, right? Right??
QNX From The Board Up Series
Learn about the relationship with physical memory addresses and how we can leverage that to finally draw something on the screen!
QNX From The Board Up Series
Another quick detour to talk about free() and releasing memory.
QNX From The Board Up Series
Let's find the boundaries for virtual memory addresses then see what happens if you try to push past them!
QNX From The Board Up Series
In this second post about memory allocation, we take a look at memory management units (MMUs), and virtual and physical addressing.
QNX From The Board Up Series
Take an introductory look at mmap() to allocate memory, then use it to write your own version of malloc(). (And build a KISS version of cat for your custom image!)
QNX From The Board Up Series
Enjoy this quick detour from our regularly-scheduled program for a (fun!) look at inspecting the kernel (and other processes) to see exactly what's running and how they are communicating.
QNX From The Board Up Series
Take a look at the relationship between the "Kernel" (aka "kernel code") and the "Kernel Process".
QNX From The Board Up Series
Learn about the asynchronous side of message-based IPC on QNX: pulses.
QNX From The Board Up Series
Take a look at sending, receiving, and replying to messages using message-based IPC provided by QNX kernel calls.