aboutsummaryrefslogtreecommitdiff
path: root/amforth-6.5/common/lib/multitask-semaphore.frt
diff options
context:
space:
mode:
authorDimitri Sokolyuk <demon@dim13.org>2017-08-19 12:15:28 +0200
committerDimitri Sokolyuk <demon@dim13.org>2017-08-19 12:15:28 +0200
commit67d25d837ac55f28a366c0a3b262e439a6e75fc3 (patch)
treedf7715c7724c5935ab87c807f3b8b4ef529315e3 /amforth-6.5/common/lib/multitask-semaphore.frt
parente0d6784e89dba33226c0edb815bb974486fa7c48 (diff)
Add AmForth
Diffstat (limited to 'amforth-6.5/common/lib/multitask-semaphore.frt')
-rw-r--r--amforth-6.5/common/lib/multitask-semaphore.frt15
1 files changed, 15 insertions, 0 deletions
diff --git a/amforth-6.5/common/lib/multitask-semaphore.frt b/amforth-6.5/common/lib/multitask-semaphore.frt
new file mode 100644
index 0000000..3b9cca4
--- /dev/null
+++ b/amforth-6.5/common/lib/multitask-semaphore.frt
@@ -0,0 +1,15 @@
+\ Semaphores (Source: B. Rodriguez)
+\ cvariable sem1
+\ : read sem1 wait do-something sem1 signal ;
+\ do-something has the ressource controlled by sem1 exlusivly
+\ wait can be used to communicate with interrupt service routines too
+\
+: wait ( addr - )
+ begin pause dup c@ until \ wait for non-zero = available
+ 0 swap c!
+;
+
+: signal ( addr -- )
+ 1 swap c! \ non-zero means available
+;
+