Summer Of CardIAC
Translation Team Alert!!!!<\/p>\n
I have started working on a PrintYourOwn version based on several existing documents. I have pulled together the text and words I want to put on this version which I am calling the Teachers\/Educators Edition. <\/p>\n
Here is the text file of the English Text. If you are able we need as many translations as we can get. I will take your translated files and construct language specific versions .<\/p>\n
Thanks in advance\u2026
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CARDIAC (CARDboard Illustrative Aid to Computation) is a learning aid developed by David Hagelbarger and Saul Fingerman for Bell Telephone Laboratories in 1968 to teach high school students how computers work. The kit consists of an instruction manual and a die-cut cardboard "computer".<\/p>\n
The computer "operates" by means of pencil and sliding cards. Any arithmetic is done in the head of the person operating the computer. The computer operates in base 10 and has 100 memory cells which can hold signed numbers from 0 to \u00c2\u00b1999. It has an instruction set of 10 instructions which allows CARDIAC to add, subtract, test, shift, input, output and jump.<\/p>\n
Hardware
The \u00e2\u20ac\u0153CPU\u00e2\u20ac\u009d of the computer consists of 4 slides that move various numbers and arrows to have the flow of the real CPU (the user's brain) move the right way. They have one flag (+\/-), affected by the result in the accumulator.<\/p>\n
Memory consists of the other half of the cardboard cutout. There are 100 cells. Cell 0 is \u00e2\u20ac\u0153ROM\u00e2\u20ac\u009d, always containing a numeric "1"; cells 1 to 98 are \u00e2\u20ac\u0153RAM\u00e2\u20ac\u009d; available for instructions and data; and cell 99 can best be described as \u00e2\u20ac\u0153EEPROM\u00e2\u20ac\u009d.
Memory cells hold signed decimal numbers from 0 to \u00c2\u00b1999 and are written with a pencil. Cells are erased with an eraser. A \u00e2\u20ac\u0153bug\u00e2\u20ac\u009d is provided to act as a program counter, and is placed in a hole beside the current memory cell.<\/p>\n
Programming
CARDIAC has a 10 instruction machine language. An instruction is three decimal digits (the sign is ignored) in the form OAA. The first digit is the op code (O); the second and third digits are an address (AA). Addressing is one of accumulator to memory absolute, absolute memory to accumulator, input to absolute memory and absolute memory to output.<\/p>\n
High level languages have never developed for CARDIAC, since they would defeat one of the purposes of the device: to introduce concepts of assembly language programming.
Programs are hand assembled then are penciled into the appropriate memory cells.
Instruction Set<\/p>\n
CARDIAC Instruction Set
Opcode Mnemonic Instruction Description
0 INP Input Take a number from the input card and put it in a specified memory cell.
1 CLA Clear & Add Clear the accumulator and add the contents of a memory cell to the accumulator.
2 ADD Add Add the contents of a memory cell to the accumulator.
3 TAC Test Accum Performs a sign test on the contents of the accumulator; if minus, jump to a
specified memory cell.
4 SFT Shift Shifts the accumulator x places left, then y places right, where x is the upper
address digit and y is the lower.
5 OUT Output Take a number from the specified memory cell and write it on the output card.
6 STO Store Copy the contents of the accumulator into a specified memory cell.
7 SUB Subtract Subtract the contents of a specified memory cell from the accumulator.
8 JMP Jump Jump to a specified memory cell. The current cell number is written in cell 99. This allows for one level of subroutines by having the return be the instruction at cell 99 (which had '8' hardcoded as the first digit.
9 HRS Halt & Reset Move bug to the specified cell, then stop program execution.<\/p>\n
Operation
Programs are run by first sliding three slides so that the number in the instruction register equals the number in the memory cell the bug is sitting in. Once that was done the bug is moved to the next memory cell. The user then follows an arrow which will then tell them what to do next. This continues for all of program execution.<\/p>\n
For More Information Please Go To
Or
Memory Cells
Output
Input
Accumulator
Advance Card
Accumulator Test
Move Bug Ahead One Cell
Instruction Decoder
Bug To Cell 00
Start
Stop
Instruction Register
Move Slides To Agree With The Contents Of The Bug's Cell
Move Bug To Cell And Add Orignal Location To Cell 99
Subtract Contents Of Cell From Accumulator
Copy Accumulator To Cell
Copy Contents Of Cell To Output Card And Advance Card
Shift Accumulator Places Left Then Places Righ
Move Bug To Cell
Add Contents of Cell To Accumulator
Set Accumulator To Contents of Cell
Copy Contents Of Input Into Cell And Advnace Card
1
2
3
4
5
6
7
8
9
0
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