DMCP Development Manual

About this Development Manual

This user manual refers to special procedures and facts related to DMCP development and testing.

System key table is used to map hardware layout of keys to independent codes to ensure DMCP is able to directly use keys (like numbers, arrows etc.).

Keyboard routines are thus extended to read keys by codes or row/col placements.

This method uses only bottom right key ([+] on DM42) to enter MSC mode. So, no other keys are needed.

press RESET++|85 which unconditionally enters MSC mode
Copy KEYMAP.BIN to root directory of calc flash disk
Keymap is automatically installed after ejecting the calc disk from PC and calculator is RESET.

It has following contents:

keymap_utils/bin/keymap2layout
keymap_utils/bin/mk_keymap
keymap_utils/keymaps/base/keymap.txt
keymap_utils/keymaps/empty/keymap.bin

The file keymap_utils/keymaps/empty/keymap.bin is empty keymap for recovery of original settings.

Use following steps to create new keymap.bin file:

Take keymap_utils/keymaps/base/keymap.txt and and swap positions of key codes in this file
Check the layout by running
```
keymap2layout keymap.txt
```
which should display the layout in terms of original key names.
Generate new keymap.bin using
```
mk_keymap <KEYID> keymap.txt
```
where <KEYID> is short keymap identifier (max 8 chars).

This chapter describes special actions invoked when some keys are pressed during calc reset.

xx: Means xx key under current system key table
xx|RC: Means xx key on original DM42 keyboard at row=R, col=C, e.g. F1|11, F6|16

Table 1. RESET keys
Keys	Handles	Action	Note
RESET+`−`	PGM	Clean Reset	DM42 doesn’t load calculator state starting with 'Memory Clear' message
RESET+`F1\|11`	DMCP	DMCP Menu	Jump to DMCP menu instead of starting program
RESET+`F6\|16`	DMCP	Production diagnostics screen	Jump directly to keyboard test of diagnostics screen. Use `EXIT\|81`+`F6\|16` to leave keyboard test and enter diagnostics menu.
RESET+`+\|85`	DMCP	MSC Mode	Jump directly to USB MSC mode. After ending MSC mode by PC usual check for fw and keymap update is done. Then the calc is RESET.