FSM-55
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1. Intro
Having fun with LED matrices!
2. Connecting your board
3. Creating your message
The fun of this exercise is to create your own message and convert it to a C program.
The program is organized in three threads:
- LED thread (dynamic LED control)
- Button thread (watchdog)
- Application thread (text screen control)
The user does not need to change the low-level threads (LED and Button), only the Application thread. The data flows from Application -> (some sort of) Video RAM -> LED control
Messages are encoded in a 5 x 5 grid of LEDs. The 'led' thread loops through each column of 5x5 grid.
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Each LED is addressed as such:
- 0x00 * 0x00 * 0x00 * 0x00 * 0x00 * 0x00
- - * * * *
- - - * * *
- - - - * *
- - - - - *
Each character would be presented as:
{ 3, 0 }, /* SPACE */
{ 4, DATA55V (0x1f, 0x04, 0x04, 0x1f, 0x00) }, /* H */
{ 3, DATA55V (0x17, 0x15, 0x0f, 0x00, 0x00) }, /* A */
{ 4, DATA55V (0x1f, 0x14, 0x14, 0x08, 0x00) }, /* P */
{ 4, DATA55V (0x19, 0x05, 0x05, 0x1e, 0x00) }, /* Y */
{ 4, DATA55V (0x0e, 0x11, 0x11, 0x0a, 0x00) }, /* C */
{ 4, DATA55V (0x1f, 0x04, 0x0c, 0x13, 0x00) }, /* K */
{ 3, DATA55V (0x11, 0x1f, 0x11, 0x00, 0x00) }, /* I */
{ 4, DATA55V (0x1f, 0x08, 0x06, 0x1f, 0x00) }, /* N */
{ 4, DATA55V (0x0e, 0x11, 0x15, 0x07, 0x00) }, /* G */
{ 2, DATA55V (0x1d, 0x1c, 0x00, 0x00, 0x00) }, /* ! */
To write the expression, "Happy Hacking!", for instance:
static uint8_t hh[] = {
CHAR_H, CHAR_A, CHAR_P, CHAR_P, CHAR_Y,
CHAR_SPC,
CHAR_H, CHAR_A, CHAR_C, CHAR_K, CHAR_I, CHAR_N, CHAR_G,
CHAR_EXC,
CHAR_SPC, CHAR_SPC, CHAR_SPC,
};