Skip to content

Sun Keyboard Protocol

Jump to bottom
hasu@tmk edited this page Jul 11, 2025 · 64 revisions

TMK SUN-USB Converter

Prebuilt converter is available here: https://geekhack.org/index.php?topic=72052.0

Source code

https://github.com/tmk/tmk_keyboard/tree/master/converter/sun_usb

Discussion

https://geekhack.org/index.php?topic=105671.0

Connector

Modern Type 4 and 5 keyboards uses 8Pin mini DIN.

   ___ ___
  /  |_|  \
 / 8  7  6 \
| 5    4  3 |
 \_ 2   1 _/
   \_____/
 (receptacle)

Wiring:
Pin mini DIN        MCU
----------------------------------
1   GND             GND
2   GND             GND
3   5V
4   Mouse RX/TX     PD4
5   Keyboard RX     PD2
6   Keyboard TX     PD3
7   GND             GND
8   5V              VCC

For ATmega32U4 you will have to use other pin than PD4 for Mouse pin.

Protocol

Signal: Asynchronous, Negative logic, 1200baud, No Flow control

Frame format:

1-Start bit, 8-Data bits, No-Parity, 1-Stop bit

0      ___ ___ ___ ___ ___ ___ ___ ___ ___      
1 ____/   \___X___X___X___X___X___X___X___\_______
        S   0   1   2   3   4   5   6   7   S

AVR USART engine expects positive logic while Sun keyboard signal is negative. To use AVR UART engine you need external inverter in front of RX and TX pin. Otherwise you can use software serial to communicate the keyboard.

This firmware uses software serial by default, so you don't need any inverter. It can be still built with 'make HARDWARE_SERIAL=y' to enable hardware serial if you have inverter. You can use 74LS04 for example.

Commands From System To Keyboard

0x01 Reset
        Keyboard responds with following byte sequence:
        Success: 0xFF 0x04
        Fail:    0x7E 0x01
0x02 Bell On
0x03 Bell Off
0x0A Click On
0x0B Click Off
0x0E LED
        followed by LED status byte:
        bit: 3       2       1       0
        LED: CapsLk  ScrLk   Compose NumLk
0x0F Layout(DIP switch)
        Keyboard responds with 0xFE 0xXX
        bit: 7 6 5 4 3 2 1 0
        DIP: x 2 3 4 5 6 7 8(DIP-SW1 is always 0 on Type-5)
  • Type-5 keyboard including SHORT TYPE at least starts sending key events without Reset command.
  • SHORT TYPE KEYBOARD has no DIP switch and replies fixed value 0x22 as layout.

Commands From Keyboard To System

0xFF sent after power up
0x7F Idle(no keys are pressed)
0xFE Layout(DIP switch) Response
0xFF 0x04 Reset Response(success)
0x7E 0x01 Reset Response(failure)

Mouse Protocol

Signal: Asynchronous, Negative logic, 1200baud, No Flow control

Frame format:

1-Start bit, 8-Data bits, No-Parity, 1-Stop bit

0      ___ ___ ___ ___ ___ ___ ___ ___ ___      
1 ____/   \___X___X___X___X___X___X___X___\_______
        S   0   1   2   3   4   5   6   7   S

Data Format:

Bit  |  7  6  5  4  3  2  1  0
-----+------------------------
Byte1|  1  0  0  0  0  L  M  R
Byte2| x7 x6 x5 x4 x3 x2 x1 x0
Byte3| y7 y6 y5 y4 y3 y2 y1 y0
Byte4| X7 X6 X5 X4 X3 X2 X1 X0
Byte5| Y7 Y6 Y5 Y4 Y3 Y2 Y1 Y0

X/Y indicates movement recorded after x/y movement occured. In the end you can get total mouse movement by adding like x+X/y+Y.

Sun mouse protcol is compatible with MouseSystems 5-byte mouse protocol.

http://www.bitsavers.org/pdf/mouseSystems/300771-001_Mouse_Systems_Optical_Mouse_Technical_Reference_Models_M2_and_M3_1985.pdf

Confirmed with ball mouse COMPACT 1 model made by Logitech(FCCID:DZLNSUN1).

3-byte format

Tadpole Sparcbook 3GX uses 3-byte format. It is a laptop computer with integrated pointing device. TMK converter won't support this format.

Bit  |  7  6  5  4  3  2  1  0
-----+------------------------
Byte1|  1  x  0  0  1  L  M  R
Byte2| x7 x6 x5 x4 x3 x2 x1 x0
Byte3| y7 y6 y5 y4 y3 y2 y1 y0

Mouse support in TMK Sun Converter

The converter revision 2.8 or later has mouse suport.

For revision 2.7 or sooner you have to conect two pads with small wire like this pic.

Scan codes

Type-5

,-------.  ,---,  ,---------------. ,---------------. ,---------------.   ,-----------. ,---------------.
|  76   |  | 0F|  | 05| 06| 08| 0A| | 0C| 0E| 10| 11| | 12| 07| 09| 0B|   | 16| 17| 15| | 2D| 02| 04| 30|
`-------'  `---'  `---------------' `---------------' `---------------'   `-----------' `---------------'
,-------.  ,-----------------------------------------------------------.  ,-----------. ,---------------.
| 01| 03|  | 1D| 1E| 1F| 20| 21| 22| 23| 24| 25| 26| 27| 28| 29| 58| 2A|  | 2C| 34| 60| | 62| 2E| 2F| 47|
|-------|  |-----------------------------------------------------------|  |------------ |---------------|
| 19| 1A|  |  35 | 36| 37| 38| 39| 3A| 3B| 3C| 3D| 3E| 3F| 40| 41| 2B  |  | 42| 4A| 7B| | 44| 45| 46|   |
|-------|  |-----------------------------------------------------------|  `-----------' |-----------| 7D|
| 31| 33|  |  4C  | 4D| 4E| 4F| 50| 51| 52| 53| 54| 55| 56| 57|+58| 59 |                | 5B| 5C| 5D|   |
|-------|  |-----------------------------------------------------------|      ,---.     |-----------|---|
| 48| 49|  | 63 |+7C| 64| 65| 66| 67| 68| 69| 6A| 6B| 6C| 6D|*6F|  6E  |      | 14|     | 70| 71| 72|   |
|-------|  |-----------------------------------------------------------|  .-----------. |-----------| 5A|
| 5F| 61|  | 77 | 13| 78 |*73 |       79         |*74 |*75| 7A | 43| 0D|  | 18| 1B| 1C| |   5E  | 32|   |
`-------'  `-----------------------------------------------------------'  `-----------' `---------------'

,-------.  ,---,  ,---------------. ,---------------. ,---------------.   ,-----------. ,---------------.
|  Help |  |   |  | F1| F2| F3| F4| | F5| F6| F7| F8| | F9|F10|F11|F12|   |PrS|ScL|Pau| |Mut|VoD|VoU|Pwr|
`-------'  `---'  `---------------' `---------------' `---------------'   `-----------' `---------------'
,-------.  ,-----------------------------------------------------------.  ,-----------. ,---------------.
|Stp|Agn|  |Esc|  1|  2|  3|  4|  5|  6|  7|  8|  9|  0|  -|  =|  \|  `|  |Ins|Hom|PgU| |NmL|  /|  *|  -|
|-------|  |-----------------------------------------------------------|  |------------ |---------------|
|Prp|Und|  |Tab  |  Q|  W|  E|  R|  T|  Y|  U|  I|  O|  P|  [|  ]| Bspc|  |Del|End|PgD| |  7|  8|  9|   |
|-------|  |-----------------------------------------------------------|  `-----------' |-----------|  +|
|Frt|Cpy|  |Ctrl  |  A|  S|  D|  F|  G|  H|  J|  K|  L|  ;|  '|  Return|                |  4|  5|  6|   |
|-------|  |-----------------------------------------------------------|      ,---.     |-----------|---|
|Opn|Pst|  |Shft| +\|  Z|  X|  C|  V|  B|  N|  M|  ,|  .|  /| RO| Shift|      | 14|     |  1|  2|  3|   |
|-------|  |-----------------------------------------------------------|  .-----------. |-----------|Ent|
|Fnd|Cut|  |Caps|Alt|Gui |MHEN|      Space       |HENK|KAN| Gui|App|Alt|  | 18| 1B| 1C| |     0 |  .|   |
`-------'  `-----------------------------------------------------------'  `-----------' `---------------'

Type-3

,-------.  ,-----------------------------------------------------------.  ,-----------.
| 01| 03|  | 05| 06|     08|     0A|     0C|     0E|     10| 11| 12| 2B|  | 15| 16| 17|
|-------|  |-----------------------------------------------------------|  |-----------|
| 19| 1A|  | 1D| 1E| 1F| 20| 21| 22| 23| 24| 25| 26| 27| 28| 29| 58| 2A|  | 2D| 2E| 2F|
|-------|  |-----------------------------------------------------------|  |-----------|
| 31| 33|  |  35 | 36| 37| 38| 39| 3A| 3B| 3C| 3D| 3E| 3F| 40| 41| 42  |  | 44| 45| 46|
|-------|  |-----------------------------------------------------------|  |-----------|
| 48| 49|  |  4C  | 4D| 4E| 4F| 50| 51| 52| 53| 54| 55| 56| 57|   59   |  | 5B| 5C| 5D|
|-------|  |-----------------------------------------------------------|  |-----------|
| 5F| 61|  |   63   | 64| 65| 66| 67| 68| 69| 6A| 6B| 6C| 6D|    6E| 6F|  | 70| 71| 72|
`-------'  |-----------------------------------------------------------|  `-----------'
           | 77 | 78  |               79                  | 7A  |   13 |
           `-----------------------------------------------------------'

,-------.  ,-----------------------------------------------------------.  ,-----------.
| L1| L2|  | F1| F2|   F3  |   F4  |   F5  |   F6  |   F7  | F8| F9| BS|  | R1| R2| R3|
|-------|  |-----------------------------------------------------------|  |-----------|
| L3| L4|  |Esc|  1|  2|  3|  4|  5|  6|  7|  8|  9|  0|  -|  =|  \|  `|  | R4| R5| R6|
|-------|  |-----------------------------------------------------------|  |-----------|
| L5| L6|  | Tab |  Q|  W|  E|  R|  T|  Y|  U|  I|  O|  P|  [|  ]| Del |  | R7| R8| R9|
|-------|  |-----------------------------------------------------------|  |-----------|
| L7| L8|  | Ctrl |  A|  S|  D|  F|  G|  H|  J|  K|  L|  ;|  '| Return |  |R10|R11|R12|
|-------|  |-----------------------------------------------------------|  |-----------|
| L9|L10|  | Shift  |  Z|  X|  C|  V|  B|  N|  M|  ,|  .|  /| Shift| LF|  |R13|R14|R15|
`-------'  |-----------------------------------------------------------|  `-----------'
           |Caps| Left|             Space                 |Right|  Alt |
           `-----------------------------------------------------------'

CTCSP SHORT TYPE KEYBOARD

,---,  ,-----------------.,-----------. ,---.   ,-----------.
| 01|  |05|06|08|0A|0C|0E|| 61| 49| 33| | 30|   | 2C| 34| 60|
`---'  |10|11|12|07|09|0B|`-----------' `---'   | 42| 4A| 7B|
       `-----------------'                      `-----------'
,-----------------------------------------------------------.
| 1D| 1E| 1F| 20| 21| 22| 23| 24| 25| 26| 27| 28| 29| 58| 2A|
|-----------------------------------------------------------|
|  35 | 36| 37| 38| 39| 3A| 3B| 3C| 3D| 3E| 3F| 40| 41| 2B  |
|-----------------------------------------------------------|
|  4C  | 4D| 4E| 4F| 50| 51| 52| 53| 54| 55| 56| 57|   59   |
|-----------------------------------------------------------|
| 63 |+7C| 64| 65| 66| 67| 68| 69| 6A| 6B| 6C| 6D| 0D|14| 6E|
|-----------------------------------------------------------|
|  77  | 13   | 78|        79       | 7A| 43| 62| 18||1B| 1C|
`-----------------------------------------------------------'

,---,  ,-----------------.,-----------. ,---.   ,-----------.
|Stp|  |F1|F2|F3|F4|F5|F6||Cut|Pst|Cpy| |Pwr|   |Ins|Hom|PgU|
`---'  |F7|F8|F9|10|11|12|`-----------' `---'   |Del|End|PgD|
       `-----------------'                      `-----------'
,-----------------------------------------------------------.
|Esc|  1|  2|  3|  4|  5|  6|  7|  8|  9|  0|  -|  =|  \|  `| 
|-----------------------------------------------------------|
|Tab  |  Q|  W|  E|  R|  T|  Y|  U|  I|  O|  P|  [|  ]| Bspc|
|-----------------------------------------------------------|
|Ctrl  |  A|  S|  D|  F|  G|  H|  J|  K|  L|  ;|  '|  Return|
|-----------------------------------------------------------|
|Shft| +\|  Z|  X|  C|  V|  B|  N|  M|  ,|  .|  /|Alt|Up|Shf|
|-----------------------------------------------------------|
|Caps  |Alt   |Met|      Space      |Met|Cmp|Num|Lft||Dn|Rig|
`-----------------------------------------------------------'

Integrix

Not compatible to Sun computers.

,-------.  ,----,  ,---------------. ,---------------. ,---------------.                ,---------------.
|  76   |  | 1D |  | 05| 06| 08| 0A| | 0C| 0E| 10| 11| | 12| 07| 09| 0B|                | 15| 16| 17| 62|
`-------'  `----'  `---------------' `---------------' `---------------'                `---------------'
,-------.  ,-----------------------------------------------------------.  ,-----------. ,---------------.
| 01| 03|  | 2A| 1E| 1F| 20| 21| 22| 23| 24| 25| 26| 27| 28| 29| 58| 42|  | 02| 04| 0F| | 2D| 2E| 2F| 47|
|-------|  |-----------------------------------------------------------|  |------------ |---------------|
| 19| 1A|  |  35 | 36| 37| 38| 39| 3A| 3B| 3C| 3D| 3E| 3F| 40| 41| 2B  |  | 14| 18| 1B| | 44| 45| 46|   |  
|-------|  |-----------------------------------------------------------|  `-----------' |-----------| 7D|
| 31| 33|  |  4C  | 4D| 4E| 4F| 50| 51| 52| 53| 54| 55| 56| 57|   59   |                | 5B| 5C| 5D|   |  
|-------|  |-----------------------------------------------------------|      ,---.     |-----------|---|
| 48| 49|  | 63 |+7C| 64| 65| 66| 67| 68| 69| 6A| 6B| 6C| 6D|  6E  | 6F|      | 34|     | 70| 71| 72|   |  
|-------|  |-----------------------------------------------------------|  .-----------. |-----------| 5A|
| 5F| 61|  | 77 | 13| 78 |    |       79         |    |   | 7A | 43| 0D|  | 73| 74| 75| |   5E  | 32|   |  
`-------'  `-----------------------------------------------------------'  `-----------' `---------------'

,-------.  ,----,  ,---------------. ,---------------. ,---------------.                ,---------------.
| Help  |  |ESC |  | F1| F2| F3| F4| | F5| F6| F7| F8| | F9|F10|F11|F12|                |Pau|PrS|ScL|NmL|
`-------'  `----'  `---------------' `---------------' `---------------'                `---------------'
,-------.  ,-----------------------------------------------------------.  ,-----------. ,---------------.
|Stp|Agn|  |  `|  1|  2|  3|  4|  5|  6|  7|  8|  9|  0|  -|  =|  \|Del|  |Ins|Hom|PgU| |  =|  /|  *|  -| 
|-------|  |-----------------------------------------------------------|  |-----------| |---------------|
|Prp|Und|  |Tab  |  Q|  W|  E|  R|  T|  Y|  U|  I|  O|  P|  [|  ]| Bspc|  |Del|End|PgD| |  7|  8|  9|   |  
|-------|  |-----------------------------------------------------------|  `-----------' |-----------|  +| 
|Frt|Cpy|  |Ctrl  |  A|  S|  D|  F|  G|  H|  J|  K|  L|  ;|  '|  Return|                |  4|  5|  6|   |  
|-------|  |-----------------------------------------------------------|      ,---.     |-----------|---|
|Opn|Pst|  |Shft| +\|  Z|  X|  C|  V|  B|  N|  M|  ,|  .|  /| Shift| LF|      | Up|     |  1|  2|  3|   |  
|-------|  |-----------------------------------------------------------|  .-----------. |-----------|Ent|
|Fnd|Cut|  |Caps|Alt|Meta|    |      Space       |    |   |Meta|Cmp|Alt|  |Lef|Dow|Rig| |      0|  .|   |  
`-------'  `-----------------------------------------------------------'  `-----------' `---------------'

Layout ID

DIP-SW configures Layout ID returned to Layout command(0x0F).

bit: 7 6 5 4 3 2 1 0
DIP: 1 2 3 4 5 6 7 8
     0 0 1 0 0 0 1 0(0x22 Unix Layout)

UNIX Layout keyboard should be configured as 0x22 with DIP-SW. Otherwise, \ key is not registered and some keys are swapped.

N860-8701-T110 with DIP-SW: 00000000

,-------.  ,---,  ,---------------. ,---------------. ,---------------.   ,-----------. ,---------------.
|  76   |  |-1D|  | 05| 06| 08| 0A| | 0C| 0E| 10| 11| | 12| 07| 09| 0B|   | 16| 17| 15| | 2D| 02| 04| 30|
`-------'  `---'  `---------------' `---------------' `---------------'   `-----------' `---------------'
,-------.  ,-----------------------------------------------------------.  ,-----------. ,---------------.
| 01| 03|  |-2A| 1E| 1F| 20| 21| 22| 23| 24| 25| 26| 27| 28| 29|-xx|-2B|  | 2C| 34| 60| | 62| 2E| 2F| 47|
|-------|  |-----------------------------------------------------------|  |------------ |---------------|
| 19| 1A|  |  35 | 36| 37| 38| 39| 3A| 3B| 3C| 3D| 3E| 3F| 40| 41| -58 |  | 42| 4A| 7B| | 44| 45| 46|   |
|-------|  |-----------------------------------------------------------|  `-----------' |-----------| 7D|
| 31| 33|  | -77  | 4D| 4E| 4F| 50| 51| 52| 53| 54| 55| 56| 57|   59   |                | 5B| 5C| 5D|   |
|-------|  |-----------------------------------------------------------|      ,---.     |-----------|---|
| 48| 49|  |   63   | 64| 65| 66| 67| 68| 69| 6A| 6B| 6C| 6D|  6E      |      | 14|     | 70| 71| 72|   |
|-------|  |-----------------------------------------------------------|  .-----------. |-----------| 5A|
| 5F| 61|  | -4C  | 13| 78|           79                   | 7A| 43| 0D|  | 18| 1B| 1C| |   5E  | 32|   |
`-------'  `-----------------------------------------------------------'  `-----------' `---------------'

,-------.  ,---,  ,---------------. ,---------------. ,---------------.   ,-----------. ,---------------.
|  Help |  |   |  | F1| F2| F3| F4| | F5| F6| F7| F8| | F9|F10|F11|F12|   |PrS|ScL|Pau| |Mut|VoD|VoU|Pwr|
`-------'  `---'  `---------------' `---------------' `---------------'   `-----------' `---------------'
,-------.  ,-----------------------------------------------------------.  ,-----------. ,---------------.
|Stp|Agn|  |Esc|  1|  2|  3|  4|  5|  6|  7|  8|  9|  0|  -|  =|  \|  `|  |Ins|Hom|PgU| |NmL|  /|  *|  -|
|-------|  |-----------------------------------------------------------|  |------------ |---------------|
|Prp|Und|  | Tab |  Q|  W|  E|  R|  T|  Y|  U|  I|  O|  P|  [|  ]| Bspc|  |Del|End|PgD| |  7|  8|  9|   |
|-------|  |-----------------------------------------------------------|  `-----------' |-----------|  +|
|Frt|Cpy|  | Ctrl |  A|  S|  D|  F|  G|  H|  J|  K|  L|  ;|  '| Return |                |  4|  5|  6|   |
|-------|  |-----------------------------------------------------------|      ,---.     |-----------|---|
|Opn|Pst|  | Shift |  Z|  X|  C|  V|  B|  N|  M|  ,|  .|  /|    Shift  |      | 14|     |  1|  2|  3|   |
|-------|  |-----------------------------------------------------------|  .-----------. |-----------|Ent|
|Fnd|Cut|  |Caps  |Alt| ◆ |          Space                 | ◆ |Com|Alt|  | 18| 1B| 1C| |     0 |  .|   |
`-------'  `-----------------------------------------------------------'  `-----------' `---------------'
  • different scan codes: -

\ is not registered with other than Layout 22h

USB HID usages

https://kentie.net/article/sunkbd/sun%20keys.txt

name sun code usb code usb name
help 0x76 0x75 help
stop 0x01 0x78 stop
again 0x03 0x79 again
props 0x19 0x76 menu
undo 0x1A 0x7A undo
front 0x31 0x77 select
copy 0x33 0x7C copy
open 0x48 0x74 execute
paste 0x49 0x7D paste
find 0x5F 0x7E find
cut 0x61 0x7B cut
mute 0x2D 0x7F mute
vol down 0x02 0x81 volume down
vol up 0x04 0x80 volume up
power 0x30 0x66 power
compose 0x43 0x65 app
left meta 0x78 0xE3 left gui
right meta 0x7A 0xE7 right gui
escape** 0x1D 0x29 escape
tilde** 0x2A 0x35 tilde
caps lock** 0x77 0x39 caps lock
control** 0x4C 0xE0 control
alt 0x13 0xE2 left alt
alt graph 0x0D 0xE6 right alt

**Escape/Tilde and control/caps lock can be swapped because these two combinations are swapped between Unix- and PC-style SUN keyboards.

Resources

SPARC Keyboard Specification

https://archive.org/details/bitsavers_sunsparcSPationVer11999_166667/

Sun keyboard to USB Converter

http://kentie.net/article/sunkbd/page2.htm

Type 3

https://web.archive.org/web/20190815152626/blog.daveastels.com.s3-website-us-west-2.amazonaws.com/2014/12/27/type-3-keyboard.html

CTCSP SHORT TYPE KEYBOARD(Type 5)

http://imgur.com/a/QIv6p

suniversal

https://codeberg.org/xelalexv/suniversal

mouse converter

http://www.rosenau-ka.de/ps2sun/

SUN Type5 keyboard USB converter

with Japanese layout support http://shikasan.net/sunkey/sunkey_e.html

Clone this wiki locally