David Knight / PololuLedStrip

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Fork of PololuLedStrip by David Grayson

PololuLedStrip.cpp@7:9a088f042ee0, 2013-03-01 (annotated)

Committer:
DavidEGrayson
Date:
Fri Mar 01 01:16:48 2013 +0000
Revision:
7:9a088f042ee0
Parent:
6:9d0530b7dae2
Child:
8:1578776ceac5
Things are still working well.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
DavidEGrayson 1:102307d9b701 1 #include "PololuLedStrip.h"
DavidEGrayson 1:102307d9b701 2
DavidEGrayson 1:102307d9b701 3 bool PololuLedStrip::interruptFriendly = false;
DavidEGrayson 1:102307d9b701 4
DavidEGrayson 7:9a088f042ee0 5 uint8_t led_strip_write_delays[3];
DavidEGrayson 4:d3b60bd43811 6
DavidEGrayson 7:9a088f042ee0 7 void PololuLedStrip::calculateDelays()
DavidEGrayson 7:9a088f042ee0 8 {
DavidEGrayson 7:9a088f042ee0 9 int fmhz = SystemCoreClock / 1000000;
DavidEGrayson 7:9a088f042ee0 10 led_strip_write_delays[0] = 700*fmhz/1000 - 25;
DavidEGrayson 7:9a088f042ee0 11 led_strip_write_delays[1] = 600*fmhz/1000 - 19;
DavidEGrayson 7:9a088f042ee0 12 led_strip_write_delays[2] = 1200*fmhz/1000 - 24;
DavidEGrayson 7:9a088f042ee0 13 }
DavidEGrayson 6:9d0530b7dae2 14
DavidEGrayson 1:102307d9b701 15 PololuLedStrip::PololuLedStrip(PinName pinName)
DavidEGrayson 1:102307d9b701 16 {
DavidEGrayson 1:102307d9b701 17 gpio_init(&gpio, pinName, PIN_OUTPUT);
DavidEGrayson 7:9a088f042ee0 18 calculateDelays(); // Assumption
DavidEGrayson 1:102307d9b701 19 }
DavidEGrayson 1:102307d9b701 20
DavidEGrayson 1:102307d9b701 21 void PololuLedStrip::write(rgb_color * colors, unsigned int count)
DavidEGrayson 1:102307d9b701 22 {
DavidEGrayson 1:102307d9b701 23 __disable_irq(); // Disable interrupts temporarily because we don't want our pulse timing to be messed up.
DavidEGrayson 7:9a088f042ee0 24
DavidEGrayson 1:102307d9b701 25 while(count--)
DavidEGrayson 1:102307d9b701 26 {
DavidEGrayson 1:102307d9b701 27 led_strip_write_color(colors++, gpio.reg_set, gpio.reg_clr, gpio.mask);
DavidEGrayson 1:102307d9b701 28
DavidEGrayson 1:102307d9b701 29 if (interruptFriendly)
DavidEGrayson 1:102307d9b701 30 {
DavidEGrayson 1:102307d9b701 31 __enable_irq();
DavidEGrayson 1:102307d9b701 32 __nop();
DavidEGrayson 1:102307d9b701 33 __nop();
DavidEGrayson 1:102307d9b701 34 __nop();
DavidEGrayson 1:102307d9b701 35 __disable_irq();
DavidEGrayson 1:102307d9b701 36 }
DavidEGrayson 1:102307d9b701 37 }
DavidEGrayson 1:102307d9b701 38
DavidEGrayson 1:102307d9b701 39 __enable_irq(); // Re-enable interrupts now that we are done.
DavidEGrayson 1:102307d9b701 40 wait_us(24); // Hold the line low for 24 microseconds to send the reset signal.
DavidEGrayson 1:102307d9b701 41 }