Differences

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--- en:pfw:multi_tasker [2025-02-27 10:56] – [Cooperative multitasker] willem
+++ en:pfw:multi_tasker [2025-03-14 13:30] (current) – [Contributions] willem
@@ Line 196: / Line 196: @@
 ==== Implementation specific and example ====
-This part is system specific (noForth t) and it's just an sample implementation:\\
+This part is system specific (noForth t) and it's just a sample implementation:\\
 <code forth>
 \ Redefine teminal I/O and MS to include multitasker
@@ Line 273: / Line 273: @@
 **Primitives for noForth t on the RP2040**
-Note that it is code directly from the noForth t metacompiler listing. So
+Note that this is code directly from the noForth t metacompiler listing.\\
-take there there are some meta specific words in it like ''>box'' & ''tp>'' etc.
+So take there there are some meta specific words in it like ''>box'', ''box>'' & ''tp>''.\\
 <code forth>
 code PAUSE      ( -- ) \ 29 machine cycles, is 0.232 microsec. at 125 MHz
-    { ip sp tos } push,     \ 4 - Save Forth environment
+    { ip sp tos } push,     \ 4 - Save tasks Forth environment
     sun TP mov,             \ 1 - TCB address to SUN
     day rp mov,             \ 1 - RP to DAY
-    day  sun 0C #) str,     \ 2 - DAY to RP
+    day  sun 0C #) str,     \ 2 - DAY TRP !
     begin, >box
     begin,                  \ An inactive task takes 7 cycles extra = 0.056 µs
@@ Line 288: / Line 289: @@
     =? no until,            \ 2 - Not zero?
     TP sun mov,             \ 1 - Next link address = new TCB
-    day  sun 0C #) ldr,     \ 2 - RP @ to DAY
+    day  sun 0C #) ldr,     \ 2 - TRP @ to DAY
     rp day mov,             \ 1 - DAY to RP
-    { ip sp tos } pop,      \ 4 - Restore Forth environment
+    { ip sp tos } pop,      \ 4 - Restore tasks Forth environment
     begin, >box
     next,                   \ 6
@@ Line 296: / Line 297: @@
 code STOP   ( -- )
-    tp> ,
+    tp> ,  ( Address of main TCB )
 code>
-    w  w ) ldr,             \ 2 - main to W
+    w  w ) ldr,             \ 2 - main TCB to W
     sun TP mov,             \ 1 - Task to DAY
     sun w cmp,              \ 1 - main = task?
@@ Line 306: / Line 307: @@
     { ip sp tos } push,     \ 4 - Save this tasks Forth environment
     w rp mov,               \ 1 - RP to W
-    w  sun 0C #) str,       \ 2 - W to RP
+    w  sun 0C #) str,       \ 2 - W to TRP
   box> again,               \ 2 - Switch to next task
 end-code
 code SLEEP  ( task -- )
-    tp> ,
+    tp> ,  ( Address of main TCB )
 code>
-    w  w ) ldr,             \ 2 - main to W
+    w  w ) ldr,             \ 2 - main TCB to W
     tos w cmp,              \ 1 - main = task?
     =? no if, >box          \ 2 - No = continue, yes = ready
@@ Line 334: / Line 335: @@
     { ip sp } push,         \ Save noForth registers
     moon rp mov,            \ Save RP
-    ip sun mov,             \ Ip to IP
+    ip sun mov,             \ IP from stack to IP
-    day tos 20 #) ldr,      \ Read R0 to DAY
+    day tos 20 #) ldr,      \ Read TR0 to DAY
-    rp day mov,             \ Use R0 as tasks RP
+    rp day mov,             \ Use TR0 as tasks RP
-    sp tos 24 #) ldr,       \ Set SP to S0
+    sp tos 24 #) ldr,       \ Use TS0 as tasks SP
     { ip sp tos hop } push, \ Initialise tasks return stack
     day rp mov,             \ Copy RP to DAY
-    day  tos 0C #) str,     \ Set tasks RP too
+    day  tos 0C #) str,     \ Set tasks TRP too
     rp moon mov,            \ Restore noForth registers
     { ip sp } pop,