May 2 A great start to May! - I've just received two XO 1.5s from OLPC Australia to further assist me in my work.

Martin and I are slowly but surely working through all the published activities to bring them all into line with the "new wave" approach. It's painstaking work - every little change always seems to have unexpected side effects - sadly, this is part and parcel of computer programming.

Activity No 22 - IQ

But I'm still finding time to come up with new activities!

Activity No 23 - Sokoban

May 5 Another old favourite but you'll see that I've enlisted the turtle as the worker

My activity has 81 puzzles ranging from easy to very difficult.

May 8 Sokoban is finished. As you can see I've reduced the number of puzzles to 26. I've also created 6 very easy puzzles for starters - you can see the first one here. The buttons allow the puzzler to watch a solution take place.

Sokoban can be played in either tablet mode or pointer mode although the latter is required to access the solution demo.

Activity No 24 - Soma

May 11 Ever onwards! Moving Ominoes into the 3rd dimension has been a tough undertaking but I'm well pleased with the result. Any similarity with children's building blocks is entirely intentional! The activity is restricted to 4 (pictured) and 5 blocks.

I still have the buttons to label and to implement tablet mode.

May 15 Soma is finished. The picture shows the 5 block marathon completed.

Activity No 25 - SimCom

May 22 Whenever I learn a new computer language, one of the first things I do is to program my simple computer simulation which I call SimCom.

So ... here goes in Python AND in the Sugar environment. The picture shows SimCom producing a list of prime numbers - not a bad effort when you realise that it can only add and subtract numbers!

SimCom has 18 instructions (Assembler equivalents in brackets):
   0 halt (HLT).
   2 return from subroutine (RTS).
   3 load the accumulator with the number in the next box (LDA #).
   5 add the number in the next box to the accumulator (ADD #).
   6 subtract the number in the next box from the accumulator (SUB #)
 1AA input a number from the keypad into box AA (INP).
 2AA output the number in box AA to the screen (OUT).
 3AA copy the number in box AA into the accumulator (LDA).
 4AA copy the number in the accumulator into box AA (STA).
 5AA add the number in box AA to the accumulator (ADD).
 6AA subtract the number in box AA from the accumulator (SUB).
 7AA jump to box AA (JMP).
 8AA jump to the subroutine starting at box AA (JSR).
 9AA branch to box AA if the accumulator is negative (BMI).
10AA branch to box AA if the accumulator is equal to zero (BEQ).
11AA branch to box AA if the accumulator is positive (BPL).
12AA add one to box AA (INC).
13AA subtract one from box AA (DEC).

Not sure where I'll go with this activity - may be too difficult to convey the instruction set using only pictures - we'll see!

May 30 Almost finished the published activities upgrade. Here's the latest report from Sugar Labs. Just the activities in blue still to go. The report also shows how many downloads.

 18,436 Castle 23
 15,226 Spirolaterals 22
 13,298 Follow Me 22
 11,849 Jumble 22
 11,007 Numbers 25
 10,668 Turtle Machine 22
  9,751 Sudoku 10
  6,490 Tessellations 23
  6,262 Boxes 22
  4,181 Eleusis 22
  3,990 Mancala 22
  3,058 Ominoes 9
  2,773 PJ Lite 22
  2,710 Trails 23
  2,610 PJ 22
  2,016 Rectangles 23
  1,901 Shapes 7
  1,172 Appel Haken 4
127,398 TOTAL DOWNLOADS
     18 ACTIVITY COUNT

Then we have seven new activities to fully test and upload:

PMJ, Triples, Pursuit, IQ, Sokoban, Soma and SimCom