add neopixel support

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hathach 2018-11-23 15:00:59 +07:00
parent 4f48b8b51a
commit 12d68f592c
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GPG Key ID: 2FA891220FBFD581
3 changed files with 132 additions and 19 deletions

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@ -35,6 +35,7 @@
/**************************************************************************/ /**************************************************************************/
#include "boards.h" #include "boards.h"
#include "nrf_pwm.h"
#include "app_scheduler.h" #include "app_scheduler.h"
#include "app_timer.h" #include "app_timer.h"
@ -83,7 +84,11 @@ void board_init(void)
// use neopixel for use enumeration // use neopixel for use enumeration
#ifdef LED_NEOPIXEL #ifdef LED_NEOPIXEL
extern void neopixel_init(void);
neopixel_init();
uint8_t grb[] = { 0, 255, 0 };
neopixel_write(grb);
#endif #endif
// Init scheduler // Init scheduler
@ -98,6 +103,11 @@ void board_teardown(void)
// Disable and reset PWM for LED // Disable and reset PWM for LED
led_pwm_teardown(LED_RED); led_pwm_teardown(LED_RED);
#ifdef LED_NEOPIXEL
extern void neopixel_teardown(void);
neopixel_teardown();
#endif
led_off(LED_BLUE); led_off(LED_BLUE);
led_off(LED_RED); led_off(LED_RED);
@ -119,25 +129,26 @@ uint32_t tusb_hal_millis(void)
return ( ( ((uint64_t)app_timer_cnt_get())*1000*(APP_TIMER_CONFIG_RTC_FREQUENCY+1)) / APP_TIMER_CLOCK_FREQ ); return ( ( ((uint64_t)app_timer_cnt_get())*1000*(APP_TIMER_CONFIG_RTC_FREQUENCY+1)) / APP_TIMER_CLOCK_FREQ );
} }
void pwm_teardown(NRF_PWM_Type* pwm )
{
pwm->TASKS_SEQSTART[0] = 0;
pwm->ENABLE = 0;
pwm->PSEL.OUT[0] = 0xFFFFFFFF;
pwm->MODE = 0;
pwm->COUNTERTOP = 0x3FF;
pwm->PRESCALER = 0;
pwm->DECODER = 0;
pwm->LOOP = 0;
pwm->SEQ[0].PTR = 0;
pwm->SEQ[0].CNT = 0;
}
void led_pwm_init(uint32_t led_pin) void led_pwm_init(uint32_t led_pin)
{ {
NRF_PWM_Type* pwm = (led_pin == LED_RED) ? NRF_PWM0 : NRF_PWM1; pwm_teardown ((led_pin == LED_RED) ? NRF_PWM0 : NRF_PWM1);
pwm->MODE = PWM_MODE_UPDOWN_UpAndDown;
pwm->COUNTERTOP = PWM_MAXCOUNT;
pwm->PRESCALER = PWM_PRESCALER_PRESCALER_DIV_128;
pwm->DECODER = PWM_DECODER_LOAD_Individual;
pwm->LOOP = 0;
pwm->SEQ[0].PTR = (uint32_t) (led_pin == LED_RED ? _pwm_red_seq : _pwm_blue_seq);
pwm->SEQ[0].CNT = PWM_CHANNEL_NUM; // default mode is Individual --> count must be 4
pwm->SEQ[0].REFRESH = 0;
pwm->SEQ[0].ENDDELAY = 0;
pwm->PSEL.OUT[0] = led_pin;
pwm->ENABLE = 1;
pwm->TASKS_SEQSTART[0] = 1;
} }
void led_pwm_teardown(uint32_t led_pin) void led_pwm_teardown(uint32_t led_pin)
@ -186,3 +197,92 @@ void led_red_blink_fast(bool enable)
} }
} }
#if LED_NEOPIXEL
// WS2812B (rev B) timing is 0.4 and 0.8 us
#define MAGIC_T0H 6UL | (0x8000) // 0.375us
#define MAGIC_T1H 13UL | (0x8000) // 0.8125us
#define CTOPVAL 20UL // 1.25us
#define NEO_NUMBYTE 3
static uint16_t pixels_pattern[NEO_NUMBYTE * 8 + 2];
void neopixel_init(void)
{
// To support both the SoftDevice + Neopixels we use the EasyDMA
// feature from the NRF25. However this technique implies to
// generate a pattern and store it on the memory. The actual
// memory used in bytes corresponds to the following formula:
// totalMem = numBytes*8*2+(2*2)
// The two additional bytes at the end are needed to reset the
// sequence.
NRF_PWM_Type* pwm = NRF_PWM2;
// Set the wave mode to count UP
// Set the PWM to use the 16MHz clock
// Setting of the maximum count
// but keeping it on 16Mhz allows for more granularity just
// in case someone wants to do more fine-tuning of the timing.
nrf_pwm_configure(pwm, NRF_PWM_CLK_16MHz, NRF_PWM_MODE_UP, CTOPVAL);
// Disable loops, we want the sequence to repeat only once
nrf_pwm_loop_set(pwm, 0);
// On the "Common" setting the PWM uses the same pattern for the
// for supported sequences. The pattern is stored on half-word of 16bits
nrf_pwm_decoder_set(pwm, PWM_DECODER_LOAD_Common, PWM_DECODER_MODE_RefreshCount);
// The following settings are ignored with the current config.
nrf_pwm_seq_refresh_set(pwm, 0, 0);
nrf_pwm_seq_end_delay_set(pwm, 0, 0);
// The Neopixel implementation is a blocking algorithm. DMA
// allows for non-blocking operation. To "simulate" a blocking
// operation we enable the interruption for the end of sequence
// and block the execution thread until the event flag is set by
// the peripheral.
// pwm->INTEN |= (PWM_INTEN_SEQEND0_Enabled<<PWM_INTEN_SEQEND0_Pos);
// PSEL must be configured before enabling PWM
nrf_pwm_pins_set(pwm, (uint32_t[] ) { LED_NEOPIXEL, 0xFFFFFFFFUL, 0xFFFFFFFFUL, 0xFFFFFFFFUL });
// Enable the PWM
nrf_pwm_enable(pwm);
}
void neopixel_teardown(void)
{
pwm_teardown(NRF_PWM2);
}
// write 3 bytes color to a built-in neopixel
void neopixel_write (uint8_t *pixels)
{
uint16_t pos = 0; // bit position
for ( uint16_t n = 0; n < NEO_NUMBYTE; n++ )
{
uint8_t pix = pixels[n];
for ( uint8_t mask = 0x80; mask > 0; mask >>= 1 )
{
pixels_pattern[pos] = (pix & mask) ? MAGIC_T1H : MAGIC_T0H;
pos++;
}
}
// Zero padding to indicate the end of sequence
pixels_pattern[++pos] = 0 | (0x8000); // Seq end
pixels_pattern[++pos] = 0 | (0x8000); // Seq end
NRF_PWM_Type* pwm = NRF_PWM2;
nrf_pwm_seq_ptr_set(pwm, 0, pixels_pattern);
nrf_pwm_seq_cnt_set(pwm, 0, sizeof(pixels_pattern)/2);
nrf_pwm_event_clear(pwm, NRF_PWM_EVENT_SEQEND0);
nrf_pwm_task_trigger(pwm, NRF_PWM_TASK_SEQSTART0);
}
#endif

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@ -14,6 +14,7 @@
#include <stdbool.h> #include <stdbool.h>
#include <stdint.h> #include <stdint.h>
#include <string.h>
#include "nrf_gpio.h" #include "nrf_gpio.h"
#if defined BOARD_FEATHER_NRF52840_EXPRESS #if defined BOARD_FEATHER_NRF52840_EXPRESS
@ -71,6 +72,10 @@ void led_pwm_enable(uint32_t led_pin);
void led_red_blink_fast(bool enable); void led_red_blink_fast(bool enable);
#ifdef LED_NEOPIXEL
void neopixel_write(uint8_t *pixels);
#endif
//--------------------------------------------------------------------+ //--------------------------------------------------------------------+
// BUTTONS // BUTTONS
//--------------------------------------------------------------------+ //--------------------------------------------------------------------+

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@ -46,6 +46,8 @@
#include "tusb.h" #include "tusb.h"
#include "usb_desc.h" #include "usb_desc.h"
#include "boards.h"
//--------------------------------------------------------------------+ //--------------------------------------------------------------------+
// MACRO TYPEDEF CONSTANT ENUM DECLARATION // MACRO TYPEDEF CONSTANT ENUM DECLARATION
//--------------------------------------------------------------------+ //--------------------------------------------------------------------+
@ -155,11 +157,17 @@ void usb_teardown(void)
//--------------------------------------------------------------------+ //--------------------------------------------------------------------+
void tud_mount_cb(void) void tud_mount_cb(void)
{ {
#ifdef LED_NEOPIXEL
uint8_t grb[] = { 255, 0, 0 };
neopixel_write(grb);
#endif
} }
void tud_umount_cb(void) void tud_umount_cb(void)
{ {
#ifdef LED_NEOPIXEL
uint8_t grb[] = { 0, 255, 0 };
neopixel_write(grb);
#endif
} }