Proposition of method of drawing Electronic Schematics
        in Ascii for purposes of Gopherspace.
	        ver. ESiA-2019:1801

Author: pVinc - Pater Vincentius

1. Why ESiA - Electronic Schematics in Ascii?
Why is the question that most likely will arise first in
your mind. So why do it? While there is a lot of CAD 
software either propertiary or FOSS the Gopher protocol
doesn't really provide any way to view the schematic
other than opening the image in an external application.
And while it is not a flaw, for Gopher was not intended
for that purpose, there might come such a time, when
CAD software would not be available for unknown reasons.

2. Codepage
ESiA is intended to be used with DOS CP437, this ensures
compatibilty with most of the available single-byte
encoded codepages. Usage of Unicode is not recommended.

3. Specification
3.1. Physical quantities symbols
    Voltage    [+/-]xxxV  (e.g. +5V, 0.4kV)
               Uxx        (e.g. U1, U2, etc.)

    Current    [-]xxxA    (e.g. 10A, 500mA)
               Ixx        (e.g. I1, I2, etc.)

    Resistance xyz where:
               x - first digit,
               y - second digit,
               z - multiplier,
               (10x+y)*10^z,
                          (e.g. 103=10kOhm)

               xRy where:
               x - integer number
               y - decimal
               x.y        (e.g. 4R7 = 4.7 Ohm)

               Rxx        (e.g. R1, R5, etc.)

    Capacitance Same as resistance, replace R with C

    Inductance Same as resistance, replace R with L

    Elements not specified in this paragraph, may be
    signified with any symbol other than the ones
    described above, and have to be specified in a
    nameplate under schematic.

    Element labels do not have to be named on the
    schematic unless neccesary. (e.g. LED diodes not
    having their symbols on schematic like
    D1, D2, D3...)

3.2. Schematic nameplate

    :              37 chars             :    19 chars     :
  ..+-----------------------------------+-----------------+
  3 |AUTHOR                             |NORM             |
  ..+-----------------------------------+-----------------+
    |SCHEMATIC TITLE                                      |
    +-----------------------------------------------------+
    |SYMBOL SPECIFICATIONS                                |
                              .
                              .
                              .

3.3. Basic symbol set
    Horizontal line    _

    Vertical line      |

    Junction           +

    Power Source       ^ U

3.4. Compound symbol set
    ground             |
                      ---

    NO SPST switch    _/_

    NC SPST switch    _-_

    horizontal        _[xyz]_ or
    resistor          _[Rxx]_

    horizontal        _|xyz|_ or
    capacitor         _|Cxx|_

    horizontal        _{xyz}_ or
    inductor          _{Lxx}_

    vertical          |    |
    resistor          # or # 
                      x    R
                      y    x
                      z    x
                      #    #
                      |    |

    vertical          |    |
    capacitor         _ or _
                      x    C
                      y    x
                      z    x
                      _    _
                      |    |

    vertical          |    |
    inductor          { or {
                      x    L
                      y    x
                      z    x
                      }    }
                      |    |

 
    potentiometer      |   _%_  |    |
                      _%_   |   %_  _%
                                |    |

    (note: potentiometer MUST be named and
    described in the nameplate, with
    its position in % and resistance in ohms)

    diode             _>|_  _|<_  |  |
                                  _  V
                                  ^  T
                                  |  |

    LED diode         _>"|_ _|"<_ |  |
                                  _  V"
                                  ^" T
                                  |  |

    Photodiode        _>*|_ _|*<_ |  |
                                  _  V*
                                  ^* T
                                  |  |
                         
    bipolar             |  
    transistor        _|     _-_ >_  
    (NPN)               v      |                             
                        |

    bipolar             |
    transistor        _|     _-_<_
    (PNP)               ^      |
                        |

    MOSFET               |    __#__
    transistor        _>|=      ^
    (n-channel)          |      |

    MOSFET
    transistor           |    __#__
    (p-channel)       _<|=      v
                         |      |

                       ______
    IC               _|P1  P4|_
                     _|P2  P3|_
                      |ICNAME|
                      |______|

    (note: there should be at least one
     space character between pin names,
     refer to example circuit)
                         
4. Example circuit

                            ^ +5V
                            |
        ____________________+
       |     _________      |
       +__/_|A7   VCC |_____+ 
       +__/_|A6   A8  |_/___+
       +__/_|A5   A9  |_/___+
       +__/_|A4   R/!W|_/___+
       +__/_|A3   !OE |_/___+
       +__/_|A2   A10 |_/___+
       +__/_|A1   !CS |_/___+
       +__/_|A0   I/O8|_________
 ______|__ _|I/O0 I/O7|_______  |
|  ___ |__ _|I/O1 I/O6|_____  | |
| |  __|__ _|I/O2 I/O5|___  | | |
| | |  +____|GND  I/O4|_  | | | |
| | |  |    |   IC1   | | | | | |
# # #  |    |_________| # # # # #
1 1 1  |                1 1 1 1 1
0 0 0  |                0 0 0 0 0
2 2 2  |                2 2 2 2 2
# # #  |                # # # # #
| | |  |                | | | | |
V"V"V" |                V"V"V"V"V"
T T T  |                T T T T T 
|_+_+__+________________+_+_+_+_|
       |
      ---

+------------------------------------+-----------------+
|pVinc                               |ESiA-2019:1801   |
+------------------------------------+-----------------+
|SRM2016C20 improvised control circuit                 |
+------------------------------------------------------+
|IC1 - SRM2016C20 SRAM circuit                         |
+------------------------------------------------------+