September 2017 Update

Task/Even-or-odd/EDSAC-order-code/even-or-odd.edsac

@@ -0,0 +1,33 @@
+[ Even or odd
+  ===========
+
+  A program for the EDSAC
+
+  Determines whether the number stored at
+  address 15@ is even or odd, and prints
+  'E' or 'O' accordingly
+
+  Works with Initial Orders 2 ]
+
+       T56K   [ load point ]
+       GK     [ base address ]
+
+       O11@   [ print letter shift ]
+       T10@   [ clear accumulator ]
+       H15@   [ multiplier := n ]
+       C12@   [ acc +:= mult AND 1 ]
+       S12@   [ acc -:= 1 ]
+       G8@    [ branch on negative ]
+       O14@   [ print 'O' ]
+       ZF     [ halt ]
+[ 8 ]  O13@   [ print 'E' ]
+       ZF     [ halt ]
+
+[ 10 ] P0F    [ used to clear acc ]
+[ 11 ] *F     [ letter shift character ]
+[ 12 ] P0D    [ const: 1 ]
+[ 13 ] EF     [ character 'E' ]
+[ 14 ] OF     [ character 'O' ]
+[ 15 ] P18D   [ number to test: 37 ]
+
+       EZPF   [ branch to load point ]