keyboard/pana_m8/README

   1 Panasonic VP-0187A
   2 ==================
   3 It is unknown keyboard from Panasonic
   4
   5 6P6C connector
   6
   7 Hirose Cheery M8 switches
   8 https://deskthority.net/wiki/Cherry_M8
   9
  10
  11
  12 Scan
  13 ----
  14 The keyboard is comprised of some of 4000 series IC without microcontroller.
  15
  16
  17     RST>-----------+---------------+
  18                    |               |
  19             TC4520 |        TC4520 |
  20             --------- carry ---------
  21     CLK>--->|row    |------>|col    |
  22             |counter|Q3     |counter|
  23             ---------       ---------
  24              Q012            Q012
  25               |||             |||
  26               |||             ABC   TC4028
  27               |||           ---------
  28               |||           |decoder|
  29               |||           ---------
  30               |||            |||||| col[0..7]
  31               ABC            vvvvvvv   pull down
  32             ---------- <----|+++++++|--100K--+
  33             |data    | <----|+++++++|--100K--+
  34     STATE<--|selector| <----|+++++++|--100K--+
  35             | 7 to 1 | <----|+++++++|--100K--+
  36             ---------- <----|+++++++|--100K--+
  37                   row[0..7]                  |
  38                              8x8 matrix      -
  39                                             GND
  40
  41
  42
  43 Matrix
  44 ------
  45         0       1       2       3       4       5       6       7
  46     --------------------------------------------------------------------
  47     0   ESC     1       2       3       4       5       6       7
  48     1   8       9       0       -       ^       BS      INS     DEL
  49     2   TAB     Q       W       E       R       T       Y       U
  50     3   I       O       P       @       [       ]       F2      F1
  51     4   CTRL    A       S       D       F       G       H       J
  52     5   K       L       ;       :       RETURN  UP      F3      F4
  53     6   SHIFT   Z       X       C       V       B       N       M
  54     7   SPACE   ,       .       /       LEFT    RIGHT   DOWN    HOME
  55
  56
  57
  58 6P6C connector pinout
  59 ---------------------
  60 1. VCC
  61 2. Clock     - sends clock to binary counter TC4520
  62 3. Key State - indicates hi if key selected by counter is active
  63 4. Sense     - indicates hi if any key is active while Reset is hi.
  64 5. Reset     - resets counter and drives all column
  65 6. GND
  66
  67       123456
  68     ,--------.
  69     |        |
  70     |        |
  71     `--____--'
  72        plug
  73