Please note that these version have note been tested recently (they are from 2016, and Arduino has changed since then). I strongly recommend to use the "Micotronic Next Generation" version given above instead.
Hence, the following info is solely provided to give a historical account of the project (from 2016):
More info about the historical project here.
See busch2090.ino or busch2090-mega.ino, or
busch2090-mega-v3.inosketch for further instructions.
This project consists of two sketches. The main emulator code is in
busch2090.ino for the Uno, and busch2090-mega.ino or
busch2090-mega-v3.ino for the Mega 2560. The EEPROM has to be
initialized properly before running the emulator. Please load and run
PGM-EEPROM.ino for the Uno version, and PGM-EEPROM-MEGA.ino
for the Mega version(s) first. The EEPROM is loaded with example
ROM programs to be loaded into the emulator via the PGM key.
The busch2090-mega-v3.ino is the Busch Microtronic Mega emulator
version 3. This version uses different hardware, and it is meant to
be housed in a case. In addition, it supports the Emic 2 TTS Speech
Synthesizer module. The Emic 2 module is optional, as is the SDCard
shield. However, Mega version 1 currently requires the SDCard shield
(will be updated soon).
Also, you will find some programs in the software directory. See
below for instructions how to use them, and for a brief explanation of
the .MIC file format.
For the Uno version, busch2090.ino:
- An Arduino Uno R3
- A TM1638 module with 8 7segment digits, 8 push buttons, and 8 LEDs
- A 4x4 keypad with matrix encoding for hexadecimal input
For the Mega 2560 version, busch2090-mega.ino, you will need
- An Arduino Mega 2560 R3
- A TM1638 module with 8 7segment digits, 8 push buttons, and 8 LEDs
- A 4x4 keypad with matrix encoding for hexadecimal input
- An LCD+Keypad shield
- An optional Ethernet+SDCard shield
For the Mega 2560 version 3, busch2090-mega-v3.ino, which is meant
to be housed in a case, you will need
- An Arduino Mega 2560 R3
- A 4x4 keypad with matrix encoding for hexadecimal input
- A 3x4 telephone keypad, for function buttons and DIN input, NOT matrix encoded
- 8 LEDs and matching resistors (for 5 V)
- 4 pull-down resistors for DIN digital inputs (typical 10 kOhms)
- 4 standard signal diodes for DOT digital outputs to prevent leakage currents from external electronic circuits / experiments connected to the outputs
- 8 N.O. momentary push buttons
- A power switch
- 2 Adafruit 7Segment LED backpacks
- 2 potentiometer, one for LCD contrast (100 Ohms), one for CPU speed (200 Ohms)
- A 4x20 LCD display, standard Hitachi HD44780
- A laser-cut (or laser-printed?) face place. The blueprint / layout is in the
faceplatedirectory of this project.
The following components are optional for the Mega version 3:
- Ethernet+SDCard shield (see
#define SDCARD) - Emic 2 TTS Speech Synthesizer module (see
#define SPEECH)
Please refer to this image for an explanations of the layout and functionality of the front panel:
For the Uno version:
TM1638 module(14, 15, 16);
byte colPins[COLS] = {5, 6, 7, 8};
byte rowPins[ROWS] = {9, 10, 11, 12};
#define DIN_PIN_1 1
#define DIN_PIN_2 2
#define DIN_PIN_3 3
#define DIN_PIN_4 4
#define RESET_PIN 0
#define CPU_THROTTLE_ANALOG_PIN 5 // connect a potentiometer here for CPU speed throttle control
#define CPU_THROTTLE_DIVISOR 10 // potentiometer dependent
#define CPU_MIN_THRESHOLD 10 // if smaller than this, delay = 0
For the Mega 2560 version 1:
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);
TM1638 module(49, 47, 45);
byte rowPins[ROWS] = {37, 35, 33, 31};
byte colPins[COLS] = {36, 34, 32, 30};
#define DIN_PIN_1 22 // digital input pins read by DIN instruction
#define DIN_PIN_2 24
#define DIN_PIN_3 26
#define DIN_PIN_4 28
#define RESET_PIN 53
#define CPU_THROTTLE_ANALOG_PIN 15 // connect a potentiometer here for CPU speed throttle control
#define CPU_THROTTLE_DIVISOR 10 // potentiometer dependent
#define CPU_MIN_THRESHOLD 10 // if smaller than this, delay = 0
// these are analog values read from the LCD+Keypad shield, adjust if necessary
// the read analog values must be greater than these, they are lower bounds:
#define NOTHING_KEY 1000
#define SELECT_KEY 770
#define LEFT_KEY 540
#define DOWN_KEY 360
#define UP_KEY 160
For the Mega version 1, please note that you will have to clip or disconnect PIN 10 from the LCD+Keypad, otherwise the SDCard will not function properly. I am using extension headers for this (just bent PIN 10 out of the way such it doesn't make contact). See this image:
For the Mega 2560 version 3 - there is more freedom how to set up the hardware, but I did it as follows:
//
// optional components
//
#define SPEECH // comment out if no Emic 2 present
#define SDCARD // comment out if no SDCard shield present
//
// SDCard chip select pin 4
//
#if defined (SDCARD)
#define SDCARD_CHIP_SELECT 4
#endif
//
// serial interface Emic 2 TTS module
//
#if defined (SPEECH)
#define RX_SPEECH A8
#define TX_SPEECH 53
#endif
//
//
//
#define RESET 47 // soft reset
#define BACK 63
#define RIGHT 64
#define UP 65
#define DOWN 66
#define LEFT 67
#define CANCEL 68
#define ENTER 69
//
// status LEDs
//
#define DOT_LED_1 55
#define DOT_LED_2 56
#define DOT_LED_3 57
#define DOT_LED_4 58
#define CLOCK_LED 39
#define CLOCK_1HZ_LED 41
#define CARRY_LED 43
#define ZERO_LED 45
//
// 1 Hz clock digital output
//
#define CLOCK_OUT 6
//
// DOT digital output
//
#define DOT_1 5
#define DOT_2 3
#define DOT_3 2 // we need pin 4 for SD card!
#define DOT_4 18 // PIN 1 didn't work for hardware experiments, probably serial
//
// DIN digital input
//
#define DIN_1 17
#define DIN_2 16
#define DIN_3 15
#define DIN_4 14
//
// telephone keypad buttons for DIN input
//
#define DIN_BUTTON_1 42 // telephone keypad #
#define DIN_BUTTON_2 44 // telephone keypad 9
#define DIN_BUTTON_3 46 // telephone keypad 6
#define DIN_BUTTON_4 48 // telephone keypad 3
//
// remaining telephone keypad buttons
//
#define CCE 26 // telephone keypad *
#define RUN 28 // telephone keypad 7
#define BKP 30 // telephone keypad 4
#define NEXT 32 // telephone keypad 1
#define PGM 34 // telephone keypad 0
#define HALT 36 // telephone keypad 8
#define STEP 38 // telephone keypad 5
#define REG 40 // telephone keypad 2
//
// CPU speed throttle potentiometer
//
#define CPU_THROTTLE_ANALOG_PIN A0
#define CPU_THROTTLE_DIVISOR 10 // potentiometer dependent
#define CPU_MIN_THRESHOLD 5 // if smaller than this, CPU = max speed
#define CPU_MAX_THRESHOLD 99 // if higher than this, CPU = min speed
#define CPU_DELTA_DISP 3 // if analog value changes more than this, update CPU delay display
//
// for initialization of random generator
//
#define RANDOM_ANALOG_PIN A5
//
// LCD panel pins
//
LiquidCrystal lcd(13, 12, 11, 7, 9, 8); // we need pin 10 for SD card!
//
// 2 Adafruit 7Segment LED backpacks
//
Adafruit_7segment right = Adafruit_7segment(); // at address 0x71
Adafruit_7segment left = Adafruit_7segment(); // at address 0x70
// right.begin(0x71);
// left.begin(0x70);
//
// HEX 4x4 matrix keypad
//
#define ROWS 4
#define COLS 4
char keys[ROWS][COLS] = { // plus one because 0 = no key pressed!
{0xD, 0xE, 0xF, 0x10},
{0x9, 0xA, 0xB, 0xC},
{0x5, 0x6, 0x7, 0x8},
{0x1, 0x2, 0x3, 0x4}
};
byte colPins[COLS] = {37, 35, 33, 31}; // columns
byte rowPins[ROWS] = {29, 27, 25, 23}; // rows
Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );
This picture might provide some ideas how to set up / wire the hardware:
Also notice that there is a blueprint of the faceplate in the
faceplate directory of this project.
For the Arduino Uno and Mega version 1, the TM1638 module is used.
The push buttons of the TM1638 are the function keys of the
Microtronic, in this order of sequence, from left to right: HALT, NEXT, RUN, CCE, REG, STEP, BKP, RUN:
#define HALT 1
#define NEXT 2
#define RUN 4
#define CCE 8
#define REG 16
#define STEP 32
#define BKP 64
#define PGM 128
The 4x4 keypad keys are hex from 0 to F, in bottom-left to
top-right order. You might consider to relabel the keys on the pad
(I haven't done that):
7 8 9 A C D E F
4 5 6 B ==> 8 9 A B
1 2 3 C ==> 4 5 6 7
* 0 # D 0 1 2 3
For the Arduino Mega version 3, there is another (non-matrix encoded) telephone keypad being used, for function buttons. The mapping is as follows:
1 2 3 NEXT REG DIN4
4 5 6 ==> BKP STEP DIN3
7 8 9 ==> RUN HALT DIN2
* 0 # C/CE PGM DIN1
Microtronic's Carry and Zero flag are the LEDs 1 and 2 of the
TM1638, the 1 Hz clock LED is LED 3 (from left to right). The LEDs
5 to 8 are used as DOT outputs (set by the data out op-code
FEx). On the Mega version 3, there is no TM1638, but discrete LEDs
are used instead. See below.
Notice that the Arduino reset button will erase the emulator's program
memory. To only reset emulator while keeping the program in memory,
connect Arduino pin D0 (RX) to ground (or D53 for the Mega
version 1, or D47 for the Mega version 3, which also has N.O.
push button for that purpose).
The Arduino Uno pins D1 to D4 (or D22, D24, D24
and D26 on the Arduino Mega version 1, or the telephone keypad
keys #, 9, 6, 3 and pins D14 to D17 on the
Mega version 3), are read by the Microtronic data in op-code FDx (DIN). Connecting them to ground will set the corresponding bit to
one (high). See PGM D. On the Mega version 3, different pins are
used, see below.
Analog pin A5 on the Uno (or A15 on the Mega version 1, or
A0 on the Mega version 3), is used as a CPU speed
throttle. Connect a potentiometer to adjust the speed of the CPU.
Important: All three pins of the potentiometer need to be connected!
The center pin of the potentiometer goes to A5
(CPU_THROTTLE_ANALOG_PIN), and the outer remaining two pins
connect to 5V (VCC) and GND. Otherwise, the analog input is
left "floating" and no analog value can be read. The analogRead
should return a value between 0 and 1023; adjust the
CPU_THROTTLE_DIVISOR 10 if required. I am using a 1 kOhm
potentiometer; don't use values smaller than 1 kOhm because of the
VCC -> GND current leakage over the potentiometer.
Unlike the original Microtronic, this emulator uses the leftmost digit of the 8digit FM1638 (or of the left Adafruit LEDs backpack display on the Mega version 3) to display the current system status (the original Microtronic only featured a 6digit display). Currently, the status codes are:
H: stoppedA: enter addressP: enter op-coder: running program?: keypad input from user requestedi: entering / inspecting register viaREGt: entering clock time (PGM 3)C: showing clock time (PGM 4)
Also unlike the original Microtronic, the emulator uses blinking
digits to indicate cursor position. The CCE key works a little bit
differently, but editing should be comfortable enough.
Typical operation sequences such as HALT-NEXT-00-RUN and
HALT-NEXT-00-F10-NEXT-510-NEXT-C00-NEXT etc. will work as expected.
Also, try to load a demo program: HALT-PGM-7-RUN.
On the Mega Version 3.2., also the single step execution and
breakpoint functionalities are also implemented (function keys
STEP and BKP). These functions are not yet implemented on the
older Mega Version 1 and Uno version (I still have to sync back some
changes from Mega Version 3 to these older code bases).
Note that programs can be entered manually, using the keypad and
function keys, or you can load a fixed ROM program specified in the
Arduino sketch via the PGM button. These ROM programs are defined
in the busch2090.ino sketch as PGM7 to PGMD macros.
The Mega version 1 uses the select button (either the LCD+Keypad shield for Uno version and Mega version 1, or the discrete N.O. button with the Mega version 3) to toggle between PC + current op-code display, register display, extra-register display, and display off. Notice that the emulator slows down considerably with LCD being turned on.
For the Mega version 3, I have used a telephone keypad for the function buttons:
#define CCE 26 // telephone keypad *
#define RUN 28 // telephone keypad 7
#define BKP 30 // telephone keypad 4
#define NEXT 32 // telephone keypad 1
#define PGM 34 // telephone keypad 0
#define HALT 36 // telephone keypad 8
#define STEP 38 // telephone keypad 5
#define REG 40 // telephone keypad 2
The remaining 4 buttons can be used to provide digital input to
DIN command; in addition, there are also real digital inputs
reserved for hardware experiments:
#define DIN_BUTTON_1 42 // telephone keypad #
#define DIN_BUTTON_2 44 // telephone keypad 9
#define DIN_BUTTON_3 46 // telephone keypad 6
#define DIN_BUTTON_4 48 // telephone keypad 3
#define DIN_1 17
#define DIN_2 16
#define DIN_3 15
#define DIN_4 14
Note that on the Mega version 3, all digital inputs are set to
INPUT_PULLUP, with the exception of these DIN_1 to
DIN_4, for which external pull-down resistors have to be used:
pinMode(DIN_1, INPUT);
pinMode(DIN_2, INPUT);
pinMode(DIN_3, INPUT);
pinMode(DIN_4, INPUT);
The DOT output LEDs are discrete LEDs, and so are carry and zero
flags, 1 Hz clock, and CPU clock:
#define DOT_LED_1 55
#define DOT_LED_2 56
#define DOT_LED_3 57
#define DOT_LED_4 58
#define CLOCK_LED 39
#define CLOCK_1HZ_LED 41
#define CARRY_LED 43
#define ZERO_LED 45
For hardware experiments, there are additional outputs for DOT as
well:
#define DOT_1 5
#define DOT_2 3
#define DOT_3 2 // we need pin 4 for SD card!
#define DOT_4 18 // PIN 1 didn't work for hardware experiments, probably serial
and there is an additional output for clock 1 Hz:
#define CLOCK_OUT 6
The faceplate has four holes under the DOT LEDs for one pair of
DIN-DOT input-output cables, and three more holes to the
right, for 9 V VCC, GND, and 1 Hz clock cables.
Since there is no LCD+Keypad shield being used, there are discrete N.O. buttons that take on these functions (SD card):
#define BACK 63
#define RIGHT 64
#define UP 65
#define DOWN 66
#define LEFT 67
#define CANCEL 68
#define ENTER 69
The Mega version supports saving a memory dump to SDCard via PGM 2. Currently, the SDCard+Ethernet card shield is mandatory in Mega
version 1, but optional in Mega version 3. The LCD+Keypad shield
offers a primitive file name editor. Use Select key to confirm
current file name; Left and Right keys to move cursor, Up
and Down keys to change character at cursor position.
With the Mega version 3, there is no keypad, but discrete N.O. buttons (see above) take on the functions for SD card operations.
Files are loaded from SDCard via PGM 1. Here, the LCD+Keypad
shield is used to browse through the directory of files. Use Select
key to confirm selection, and Left key to abort loading.
The software directory contains some programs from the
Microtronic manuals and from the book "Computer Games (2094)". With
the Mega version, you can put these files on a FAT16 formatted SDCard,
and load them via PGM1. Please refer to the original manuals on
how to use these programs.
In .MIC file, in addition to hexadecimal instructions, you can
find comments (a line starting with #), as well as the origin
address instruction @ xx. This means that the instructions
following @ xx will be stored from address xx on. Most of the
time, you will find @ 00 at the beginning of the file. If a
.MIC file does not contain a @ xx, then the program will be
loaded at the current PC. That way, programs could be relocatable
(e.g., for subroutines). Also, a .MIC can contain more than one @ xx. An example is the DAYS.MIC program.
There are a couple of programs in the Microtronic Manual Vol. 2 which
require incremental loading of parts, i.e., first load DAYS.MIC,
and then additionally load WEEKDAY.MIC. The programs automatically
load at the correct addresses.
The example programs in the software directory have been
automatically converted from the above linked PDFs with the help of an
OCR (Optical Character Recognition) program, so they may contain some
strange characters and OCR artifacts and errors. Not all programs have
been tested by the author yet. Programs which have been successfully
tested contain a # tested comment. To compensate for OCR
artifacts, the .MIC loader recognizes an extended character set
for hexadecimal input, e.g., not only 1, but also I and l are accepted
for 1, the O character is accepted for 0, etc.
For the Uno version, please run the PGM-EEPROM.ino sketch first,
and use PGM-EEPROM-MEGA.ino for the Mega versions. This will load
example programs into the Arduino's EEPROM. The emulator won't
initialize correctly otherwise.
The programs stored into and loaded from the EEPROM are PGM 7 to
PGM C:
PGM 0: self-test not yet implemented.PGM 1: on Mega, this loads a program memory dump from SDCard. Use LCD+Keypad shield to select file viaSelectkey,Leftkey to abort loading.PGM 2: on Mega, this saves a complete memory dump to SDCard (.MICfile extension is used). The LCD+Keypad shield offers a simple filename editor. UseLeftandRightto change cursor position,UpandDownto change character at cursor position, andSelectto confirm and save. The files are stored as text. You can also use a simple text editor to create files (CR+LF end of line coding), and load them back viaPGM 2. Whitespace is ignored.PGM 3: set time / clock (not a real program, i.e., nothing is loaded into program memory for this function)PGM 4: show time / clock (not a real program, i.e., nothing is loaded into program memory for this function)PGM 5: clear memoryPGM 6: loadF01(NOPs) into memoryPGM 7: the Nim game as documented in the Microtronic Manual Vol. 1, page 7. Many thanks to Martin Sauter for retrieving the code from an original Busch Microtronic and contributing it to this project!PGM 8: crazy counterPGM 9: the electronic die, from Microtronic Manual Vol. 1, page 10PGM A: the three digit counter from Microtronic Manual Vol. 1, page 19PGM B: moving LED light from Manul Vol. 1, page 48PGM C: digitial inputDINtest (port input output echo)
If enabled, the Emic 2 speech module will echo back and confirm function and HEX keypad presses. In addition, the navigation buttons of the file browser trigger the following functions:
- Left : describe current system status.
- Right : describe content of 7segment display
- Up : general Microtronic emulator information
- Down : emulator software version
- Cancel : get an answer from the Magic 8-Ball
- Back: listen to HAL 9000
Also, activities such as loading a PGM or SDCard program, clearing the program memory, displaying or setting the time, are spoken.
Occasionally, the Emic 2 crashes and simply stops talking. Then, only a full power-cycle will revive it.
The built-in Emic can also be accessed programmatically be means of
Microtronic machine instructions, and hence be made to speak arbitrary
sentences. The MOV xx / code 0xx instructions are being used
for this purpose. The effect of a MOV xx instruction is to copy
the contents of register x onto itself, so these instructions are
basically vacuous, redundant NO-OPs. An extra meaning / extra effect
is given to them in the Mega version 3. Here, a MOV xx sends a
(high- or low) nibble x to the built-in Emic 2. A full ASCII
character with decimal code xy (e.g., 65 for character A) is
thus sent via 0xx, 0yy (e.g., 066, 055 for character A),
in "most significant nibble first" order. Notice that these nibbles
are decimal nibbles though, not hexadecimal nibbles. Hence, x can
take values from 0 to C (ASCII goes from 0 to 127, and 12 = C - not
all ASCII characters are speakable, of course - in fact, all
characters below 32 are ignored, with the exception of carriage
return, ASCII code 13). Decimal coding is used in order to make entry
of ASCII character codes more convenient. Notice that Emic requires a
heading S as well as a trailing carriage return (ASCII code 13).
An ABC from the Emic 2 hence takes the program 088 033 066 055 066 066 066 077 011 0033. Consequently, the Microtronic program
memory can store 126 characters max.
The emulator requires the following libraries, which are the work of
others, and which are included in the library subdirectory:
KeypadlibraryTM1638library - note that this is a modified version of the original oneTM16XXFontsfor alphanumeric 7segment display fontsEEPROMlibrary
For the Mega version 1, the following standard libraries are used, and already part of the Arduino distribution (version 1.6.6):
TM16XXFontsfrom theTM1638libraryLiquidCrystallibrarySPIlibrarySDlibraryStringlibrary
The SD and String libraries were responsible for memory leaks
and terrible system instability. I hence removed them in Mega version 3,
and switched to the fabulous SdFat library which works much more
reliably.
For the Mega version 3, the following standard libraries are used, and already part of the Arduino distribution (version 1.6.6):
TM16XXFontsfrom theTM1638libraryLiquidCrystallibrarySPIlibrarySoftwareSerialto talk to the Emic 2 TTS module
These additional Adafruit libraries are required to drive the 7Segment LED SPI backpack displays. They are available from the Adafruit homepage:
Adafruit_LEDBackpacklibraryAdafruit_GFXlibrary
In addition, instead of the SD card library, the
SdFatlibrary.