Thursday, December 31, 2099
Sunday, May 16, 2021
PicoEnigma is an Enigma Z30 simulator, a rare, numbers only Enigma Machine.
Its mode of operation is similar to other Enigma machines, it has a keyboard and a lampfield, pushing a key sends electricity to the entry rotor (ETW), then the electricity goes from right to left through the rotor pack, comes back through the reflector (UKW), and returns from left to right through another set of wires in the rotor pack, goes into the ETW and out to a lamp.
In this machine, the rotors can be rearranged, the ring setting can be changed and the rotor starting position can be set. To successfully decrypt a message, the machine settings must be the same used to enctypt it.
This simulator is designed to operate the same as the Enigma Z30 Simulator for the KIM Uno:
After the simulator is turned on, it is ready to encrypt a message. The rotor starting position is 4321. Pressing a key advances the rotors and lights the result. The result will be illuminated while the key is being pushed. Releasing the key turns the lamps off.
During machine operation, all the lamps will be off if none of the black keys are pressed, or one lamp will illuminate when a black key is pressed. Pressing the red key enters the configuration mode. To indicate at a glance that the machine is in the configuration mode, all of the lamps are lit except for one.
When only the first lamp is turned off, the rotor types are being changed. Pushing the keys above or below the displays changes the rotor type for that position. Each rotor can only be used once. Once a unique rotor combination is selected, pushing the red key again advances to the next setting.
When the second lamp is turned off, the ring settings are being changed. The up and down keys are used to change this setting, Each rotor can be set differently to a number from 0 to 9. Pressing the red menu key advances to the next setting.
When the third lamp is turned off, the stepping mode is being changed. There were two kinds of machines, one with a traditional lever stepping and another with geared stepping. The lever stepping machines suffered from a double stepping anomaly where a 9 in any position steps that wheel and the one to its left. A double stepping sequence is: 0088 0089 0090 0101 Geared stepping works like a car odometer and no digits are skipped.
The stepping mode is indicated by the digit on the right. If it shows a 0, the machine is using lever stepping, if it shows a 1, it is using geared stepping. In this screen, pushing the leftmost up and down button also changes the brightness of the lampfield digits.
Pushing the red menu button again turns all the lamps off and returns to the operating mode screen.
Pushing the up and down buttons changes the rotor starting position. The machine is now ready to encrypt numbers.
To send a text message, an encoding scheme must be devised. Either substitute letters by two numbers A 01 B 02 ... Y25 Z26 or use a codebook where words are substituted by numbers, first translate the message to numbers then encrypt the numbers.
To decrypt the message ensure the machine is set up exactly as the machine used to send the message. Ensure the starting position is set the same as well.
For example, to encrypt the message TEST, use the table below.
A B C D E F G H I J K L M
01 02 03 04 05 06 07 08 09 10 11 12 13
N O P Q R S T U V W X Y Z
14 15 16 17 18 19 20 21 22 23 24 25 26
The word TEST would be encoded as 20 05 19 20
Typing and holding one number at a time in the machine using the default settings after power up yields 44 57 43 94
The wheels should be at position 4329 after all the numbers have been typed.
To decrypt it, use the up and down keys to reset the wheels to the starting position of 4321. Then type the encrypted message (44 57 ...) and the original message (20 05 ...) will be displayed.
Thursday, January 21, 2021
This is a new project, a DSKY, the Display Keyboard interface for the Apollo Guidance Computer (AGC), using two 240x320 LCD screens and a keypad made with Kailh Cherry clone keys.
This DSKY uses an Arduino Mega 2560 to interface with the host computer via a USB Virtual Serial Port. The Arduino Mega uses two of its auxiliary serial ports to communicate with the Arduino Nano on each screen. The Arduino Mega is also responsible for scanning the DSKY keyboard and sending keypresses back to the host computer.
Each indicator on the left and right screen is controlled by a command from the host computer. For example to illuminate the indicators below, the host computer sends to the Mega the following string "C F P V00 N00 X 00000 Y 00000 Z 000 ". The Mega receives commands from the host computer and forwards them to both screens. The left screen reacts to single character commands A..O. Upper case commands illuminate an indicator, lower case commands turn them off. The right screen uses the Q command to illuminate the COMP ACTY indicator and the P, V, N, X, Y, Z commands to display numeric data which may include a leading positive or negative sign.
Friday, December 18, 2020
Sunday, October 25, 2020
Bill of Materials:
2) 1x Meduino, (Mega 2560 Pro Mini). Make sure the pins to the right and the left of the USB connector match
3) 2x 0.56 inch RED 7 SEGMENT LED DISPLAY COMMON CATHODE. Get either 2x 5161AS or 2x 5611AH
4) 1x EC11 Rotary Encoder.
5) 1x Potentiometer Cap (you may want to substitute with something more appropriate)
6) 1x 3pin spdt switch arduino
7) 20x 0.5M Audio Cable 3.5mm Male to Male 90 Degree Angle. Get the 0.5M the 20cm is too short.
8) 4x M2 25mm Female to Female Brass Standoff
Assembled Unit Pictures:
Friday, October 16, 2020
[alank2] started a class of enigma machine simulators under 10x10cm and has now announced the latest addition to this family: BinaryEnigma
This class of machines was started to take advantage of the discounted rate when ordering pcbs sized 10x10cm and under from the Far East. The original, MicroEnigma using a 2 layer board and SMT components is described here:
Another member of the family, PicoEnigma is a few millimeters smaller than MicroEnigma and uses all through hole parts, but needs a two board stack.
The smallest of the bunch, BinaryEnigma was announced in this forum post:
It appears to use an Oshpark PCB with a minimal number of components, LEDs and pushbuttons in the front and an SMT ATtiny84a in the back along with a few support components. The whole thing is powered by a CR2032 lithium battery that lasts 200 hours of machine operation.
Here are a few videos of the members of this family:
Saturday, September 12, 2020
Pico Enigma is now available in a Kit. This is very easy to assemble, with all the parts being thru-hole. The kit includes all the parts needed to assemble your own enigma machine simulator. The glue to put together the wood enclosure is not include. Gorilla Go2Gel is recommended.
For assembly instructions:
Sunday, August 16, 2020
The seven segment LED board can now drive 16 LED using only an Arduino Nano. Using the circuit described below it can drive 18 LEDs using a stock Arduino Uno/Nano and 20 if the LED on pin D13 is removed by desoldering it.
Here is a picture of the board showing the first 16 digits of PI
The first board gets two Arduinos. The first one, at the top of the board sends instructions to the second one at the bottom of the board. The bottom arduino is responsible for receiving serial instructions and driving the LEDs, If a packet received through the serial port is not meant for the current board, it gets relayed to the next board. The TX pin in the bottom Arduino is connected to the RX pin on the next board's Arduino Nano.