Added multitask example

equi.c

@@ -452,9 +452,12 @@ ushort equi_find_free_task_slot() {
 /* Find the next active task in the table, round-robin fashion */
 struct EquiCtx* equi_find_next_task() {
   ushort oldtaskid = ram.taskid; /* save the current one to avoid deadlocks */
-  while(!ram.tasks[ram.taskid].active) {
+  while(1) {
     ++ram.taskid;
-    if(ram.taskid == EQUI_TASKS_MAX) ram.taskid = 0;
+    if(ram.taskid == EQUI_TASKS_MAX)
+      ram.taskid = 0;
+    if(ram.tasks[ram.taskid].active)
+      break;
     if(ram.taskid == oldtaskid) /* found no active tasks, bailing out */
       return NULL;
   }
@@ -488,7 +491,7 @@ void equi_main_loop() {
   while(1) { /* iterate over the instructions in the command buffer */
     curtask = equi_find_next_task(); /* attempt to switch the context on every iteration */
     if(curtask == NULL) break; /* exit the main loop when no tasks are left */
-    instr = flatram[++curtask->pc];
+    instr = flatram[++(curtask->pc)];
     /* silently exit on zero or FF */
     if(instr == 0 || instr == 0xFFu)
       curtask->active = 0;

examples/multitask.equi

@@ -0,0 +1,28 @@
+(A very simple example to showcase multitasking capabilities of Equi)
+(by Luxferre, 2022, public domain)
+
+(save cmd buffer start to ease calculations)
+X1-GS
+
+(define a task multiplexer to run the second task)
+0026#GL+6#0Y!
+
+(and the third task)
+002D#GL+6#0Y!
+
+(while we define the third task, the second is already running,
+so some B's will be output even before A's,
+and when the third task will be defined, one C will be output)
+
+(define task 0 - output A in endless loop)
+A"$.5NJ
+
+(define task 1 - output B in endless loop)
+B"$.5NJ
+
+(define task 2- output C in endless loop)
+C"$.5NJ
+
+(and now, ABC pattern should print continuously)
+
+Q