Keymap Editor for TMK firmware
==============================

- [HHKB](hhkb/index.html)


Instruction
-----------


Limitation
----------


TODO & MEMO
------------
### Edit action for FN key
### Better source output
KEYMAP macro
### Actionmap support
### Macro editor
### Layer operation
copy, swap, set all, clear...
### Compress share URL
lz-string.js

### Bootloader jump doesn't work
### Better Keyobard graphic
### Keyobard layout screenshot
- HTML5 canvas
- png image file output


ldscript and Flash Memory
-------------------------
`ldscript_keymap_avr5.x` is ldscript and located at top directory. Using 

Flash Memroy Map of ATMega32U4(32KB)

    +--------------------+ 0x0000
    | .vectors           | 0xac (43vectors * 4bytes)
    | .progmem           | PROGMEM variables and PSTR
    | .init0-9           |
    | .text              | code
    | .fini9-0           |
    |                    | > text region
    |--------------------| _etext
    | .data              |
    | .bss               |
    | .noinit            |
    |                    | > data region
    |--------------------| 0x6800
    | .keymap.fn_actions |
    | .keymap.keymaps    | > keymap region(2KB)
    |--------------------| 0x7000
    | bootloader         | 4KB
    +--------------------+ 0x7FFF


Keymap(8bit code)
-----------------
`const uint16_t fn_actions[] __attribute__ ((section (".keymap.fn_actions")))`
`const uint8_t keymaps[8][ROW][COL] __attribute__ ((section (".keymap.keymaps")))`

These arrays are placed at fixed address in .keymap section:


    actions[] -> +-------------+
                 | action x 32 |
    keymaps[] -> |-------------|
                 | keymap    0 |
                 |-------------|
                 | keymap    1 |
                 |-------------|
                 | keymap    2 |
                 |-------------|
                 | keymap    3 |
                 |-------------|
                 |   :    :    |



Actionmap(16bit code)
---------------------
`const uint16_t actionmaps[] __attribute__ ((section (".keymap.actionmaps")))`

All key action can be defined in 16bit code. Memory usage will be about doubled size compared to keymap(8bit code).

    actionmaps[] -> +-------------+
                    | actionmap 0 |
                    |-------------|
                    | actionmap 1 |
                    |-------------|
                    | actionmap 2 |
                    |-------------|
                    | actionmap 3 |
                    |-------------|
                    |   :    :    |


Flash usage cosidaration
------------------------
For example of biggest ever map, PS/2 and ADB converter have 256 keys in a layer, so use 256 bytes each layer in keymap and 512 bytes in actionmap.
In most cases map size of keyboard will be far smaller than that.

### ATmega32U4

    Firmware    -24KB(with full option)
    Keymapping    4KB-
    Bootloader    4KB(Atmel stock) or 512B(Teensy)

### ATmega16U4(Not suppoeted yet)

    Firmware    -10KB
    Keymapping    2KB-
    Bootloader    4KB(Atmel stock) or 512B(Teensy)



Hex file format
---------------
[Intel Hex(wikipedia)](http://en.wikipedia.org/wiki/Intel_HEX)

### 1.Start code
    ':'

### 2.Byte Count
    2 x hex(0-FF)

### 3.Address
    4 x hex(0-FFFF)

### 4.Record Type
    2 x hex(00-05)

#### Record Type code
    00: Data record. which contains 16bit address and data.
    01: End of File record. It must appear in the last line.(usually :00000001FF)
    02: Extended Segment Address Record.
    03: Start Segment Address Record.
    04: Extended Linear Address Record. Upper two bytes of 32 bit address.
    05: Start Linear Address Record.

### 5.Data
    byte_count * hex(00-FF)

a sequence of data bytes

### 6.Checksum
    2 x hex(00-FF)

LSB of 2's complement of the sum of fields[ 'Byte Count', 'Address', 'Record Type' and 'Data' ]

`checksum = ~(the sum of bytes)&0xff + 1 = (the sum)&0xff^0xff + 1`