Bob Ammerman [rammerman at prodigy.net] of RAm Systems says
The PIC18Cxx2 chips contain quite a few nice new features. One of the neatest is programmable access to the stack. This feature allows many powerful tricks.
- this code has _NOT_ been tested!
- all multi-byte values are little-endian
- I assume the code space never exceeds 16 bits worth (which it never will on the 242, 252, 442 or 452 chips).Co-routines/cooperative tasks version 1 Note: assumes that all cocalls are from mainline code (ie: the subroutine stack is empty) CBLOCK TASKX_PC:2 ; Address of next instruction to run in task X TASKY_PC:2 ; Address of next instruction to run in task Y ENDC initialize: ; initialize values for all but the first task movlw low(tasky) movwf TASKY_PC,A movlw high(tasky) movwf TASKY_PC+1,A ...fall thru into first task... taskx: . . rcall x_cocall_y . . rcall x_cocall_y . bra taskx x_cocall_y: movff TOSL,TASKX_PC movff TOSH,TASKX_PC+1 movf TASKY_PC,W,A movwf TOSL movf TASKY_PC+1,W,A movwf TOSH return tasky: . . rcall y_cocall_x . . rcall y_cocall_x . bra tasky y_cocall_x: movff TOSL,TASKY_PC movff TOSH,TASKY_PC+1 movf TASKX_PC,W,A movwf TOSL movf TASKX_PC+1,W,A movwf TOSH return
|file: /Techref/microchip/18c/multitask-coop1-ba.htm, 1KB, , updated: 2000/10/12 12:14, local time: 2020/7/14 16:14,
|©2020 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions?|
<A HREF="http://www.piclist.com/techref/microchip/18c/multitask-coop1-ba.htm"> PIC 18C Microcontoller Program Flow Method for Co-routines/cooperative tasks mainline cocalls only</A>
|Did you find what you needed?|
PICList 2020 contributors:
o List host: MIT, Site host massmind.org, Top posters @20200714 RussellMc, Bob Blick, Jason White, Neil, David C Brown, Harold Hallikainen, madscientistatlarge, Sean Breheny, Allen Mulvey, James Cameron,
* Page Editors: James Newton, David Cary, and YOU!
* Roman Black of Black Robotics donates from sales of Linistep stepper controller kits.
* Ashley Roll of Digital Nemesis donates from sales of RCL-1 RS232 to TTL converters.
* Monthly Subscribers: Gregg Rew. on-going support is MOST appreciated!
* Contributors: Richard Seriani, Sr.
Welcome to www.piclist.com!