8051 kernel

This would be a good start point for a multitask core, there used to be a few similar codes liek Tiny51 or so, but I left them too long and can't remember much. I want a very small core like Arduino scheduler. The functions are valuable as author stated, although they are asm, user would be able to call them directly, but I don't know whether the floating format are standard, nor I know whether all math functions support floating values or just integers. All codes are assembly language, this might block some people. There is no i/f to C given. I remove one start because there is no document for source code thus incomplete. Comments are not very good - at least the i/o parameters and functionality for each function is not clearly mentioned. I remove another star because the core code is mixed with debug and serial TX/RX and ANSI escape code, I guess the author connect PC to monitor and update ports data for debug purpose, this makes the code cannot be used directly nor suitable for a real device - where user no need occupy such I/O pins nor needs ANSI or serial port. Basically, for multitask we need to use a timer interrupt to swap tasks, and to swap task we need to preserve current task's context and swap in new task's context. This program swapped internal RAM and most registers, but, it might not be used for C code as dptr seems not protected, But the code flow will help people especially for those don't know how multitask works - the code is simple enough for them to understand. I hope somebody can tell me where to find a simplest multitask core, for example three to handle main, input(like keys) and output(like LCDs), we no need to wait for key bounce and care its delay might block us. I left 8051 code for 20+ years, when I just use timer to kick in tasks. There would be no reason for so long time and no such C core on www. Thanks very much for author to share his idea and working code.