1 files changed, 63 insertions, 0 deletions
diff --git a/ldmicro/sample/var-timer.ld b/ldmicro/sample/var-timer.ld
new file mode 100644
index 0000000..a7b28fb
--- /dev/null
+++ b/ldmicro/sample/var-timer.ld
@@ -0,0 +1,63 @@
+LDmicro0.1
+CYCLE=10000
+CRYSTAL=4000000
+BAUD=2400
+
+IO LIST
+    Xin at 0
+    Yout at 0
+    Apot at 0
+END
+
+PROGRAM
+RUNG
+    COMMENT This is the actual variable-delay TOF timer. When Rdel_input goes high, Rdel_output goes high \r\nt_max cycle times later. When Rdel_input goes low, Rdel_output goes low immediately.
+END
+RUNG
+    CONTACTS Rdel_input 0
+    LEQ t_count t_max
+    ADD t_count t_count 1
+END
+RUNG
+    CONTACTS Rdel_input 1
+    MOVE t_count 0
+END
+RUNG
+    COMMENT The extra branch is to make a delay of 0 cycles work correctly.
+END
+RUNG
+    PARALLEL
+        GRT t_count t_max
+        SERIES
+            CONTACTS Rdel_input 0
+            EQU t_max 0
+        END
+    END
+    COIL Rdel_output 0 0 0
+END
+RUNG
+    COMMENT \r\n
+END
+RUNG
+    COMMENT This is just an example of how to use the timer. The voltage attached to Apot (which goes\r\nfrom 0 V to Vdd) sets the delay between when Xin goes high and when Yout goes high.
+END
+RUNG
+    READ_ADC Apot
+END
+RUNG
+    COMMENT This only works with a cycle time of 10 ms. If we want the delay to be between 0 s and 5 s,\r\nthen it should be 0 to 500 cycle times; the ADC goes from 0 to 1023, so (roughly) divide by 2.
+END
+RUNG
+    DIV t_max Apot 2
+END
+RUNG
+    COMMENT Then just hook up the input and the output of the timer to pins. Of course\r\nthat could drive more complicated logic, not just a pin on the processor.
+END
+RUNG
+    CONTACTS Xin 0
+    COIL Rdel_input 0 0 0
+END
+RUNG
+    CONTACTS Rdel_output 0
+    COIL Yout 0 0 0
+END