Libndls

libndls is a set of macros and functions available as a static library when building with Ndless. The library is automatically linked by nspire-ld if required.

These definitions are available in Ndless 2.0. Definitions marked with (asm) are only available in assembly.

Common types

• typedef enum bool {FALSE = 0, TRUE = 1} BOOL;

Data manipulation

• uint16_t bswap16(uint16_t): swap the bytes of a 2-bytes integer
• uint32_t bswap32(uint32_t): swap the bytes of a 4-bytes integer

Math

• number abs(number)
• number min(number, number)
• number max(number, number)

Screen

• SCREEN_BASE_ADDRESS: address of the screen buffer. Each grayscaled pixel is 4-bit long. 1111 is white, 0000 is black.
• SCREEN_BYTES_SIZE: size of the screen buffer
• SCREEN_WIDTH: screen width in pixels
• SCREEN_HEIGHT: screen height in pixels
• void clrscr(void): clear the screen

UI

• void show_msgbox(const char *title, const char *msg): show a message box, with a single button OK"

Keyboard

• BOOL any_key_pressed(void): non-blocking key press test. Return TRUE if one or more keys are being pressed.
• BOOL isKeyPressed(key): non-blocking key press test. key must be one of the KEY_NSPIRE_* constants defined in include/common.h.
• BOOL on_key_pressed(void): non-blocking ON key press test. Since v3.0.
• void wait_key_pressed(void): block until a key is pressed
• void wait_no_key_pressed(void): block until all the keys are released
• touchpad_info_t *touchpad_getinfo(void): return information on the Touchpad area such as its dimension. Return NULL if not a TI-Nspire Touchpad. See include/libndls.h for the definition of touchpad_info_t.
• int touchpad_scan(touchpad_report_t *report): check user interactions with the Touchpad area and writes to report. See include/libndls.h for the definition of touchpad_report_t. report->contact and report->pressed are always FALSE on TI-Nspire Clickpad. See src/arm/tests/ndless_tpad.c for an example of use.

CPU

• void clear_cache(void): flush the data cache and invalidate the instruction and data caches of the processor. Should be called before loading code dynamically, after a code patch or with self-modifying code.
• unsigned set_cpu_speed(unsigned speed): since v3.0. speed is one of CPU_SPEED_150MHZ, CPU_SPEED_120MHZ, CPU_SPEED_90MHZ. Returns the previous speed. You must restore the original speed before the program exits.

Hardware

BOOL is_touchpad : TRUE on a TI-Nspire Touchpad.

Time

• void idle(void): switch to low-power state until the next interrupt occurs. The use of this function is encouraged when waiting in loops for an event to save the batteries.
• void sleep(unsigned m): delay for a specified amount of time. The CPU is regularly switched to low-power state while blocking.

Debugging

• void halt(void): stop the execution flow with an endless loop. If you are using the Ncubate emulator, use the j debugger command to jump over the instruction.
• halt (asm) (macro): similar to halt()