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Spidey Wall is the name for a physical wall lit up by multiple addressable LED strips. This program is an LPC1768 web server to control the wall from a browser.
Dependencies: EthernetInterfacePlusHostname RdWebServer mbed-rtos mbed
This project is part of a Light-Wall using addressable LED strips (WS2801). I have published a few posts on my blog about the construction of the wall and building a game to play on it (PacMan). I have also had a guest post from a friend who has set his children the task of producing some interesting animations. The original post is http://robdobson.com/2015/07/spidey-wall/
So far, however, I hadn't fully connected the physical (and electronic) wall with the web-browser creations to drive it. This project is hopefully the final link. A fast and reliable web server using REST commands to drive the 1686 LEDs in the Spidey Wall from code running in a browser (say on an iPad while you are playing a game).
The approach taken here results in the ability to control the RGB values of all 1686 LEDs at a rate of 20 frames per second.
A blog post describing the whole thing is here:
http://robdobson.com/2015/08/a-reliable-mbed-webserver/
ledstrip.cpp
- Committer:
- Bobty
- Date:
- 2015-08-31
- Revision:
- 4:b521815f2657
- Parent:
- 3:e5ea80fae61d
- Child:
- 6:8df79fe1afcd
File content as of revision 4:b521815f2657:
// LED Strip using WS2801 with two ISRs for two SPI connected // LED strips running in parallel // Rob Dobson 2013-2014 #include "ledstrip.h" #include "colourconverters.h" #include "stddef.h" #define SPIF 0 // SPI interrupt flag bit #define SSP_IMSC_TX_RDY 3 #define SSP_IMSC_BITMASK 0x0f volatile int mCurPos0 = 0; int mEndPos0 = 0; volatile bool isr0Busy = false; unsigned char* pLedValues0 = NULL; extern "C" void spi0_isr() { if (mCurPos0 < mEndPos0) { LPC_SSP0->DR = pLedValues0[mCurPos0]; // write to FIFO data register mCurPos0++; } else { // Turn off interrupts LPC_SSP0->IMSC = 0; isr0Busy = false; } } volatile int mCurPos1 = 0; int mEndPos1 = 0; volatile bool isr1Busy = false; unsigned char* pLedValues1 = NULL; extern "C" void spi1_isr() { if (mCurPos1 < mEndPos1) { LPC_SSP1->DR = pLedValues1[mCurPos1]; // write to FIFO data register mCurPos1++; } else { // Turn off interrupts LPC_SSP1->IMSC = 0; isr1Busy = false; } } ledstrip::ledstrip(int length, int splitPoint) { mpLedValuesA = NULL; mpLedValuesB = NULL; mpCurLedValues = NULL; // SPI0 (using SSP 0 in 1768 chip) mpSPI0 = new SPI(p11, NC, p13); mpSPI0->format(8,0); mpSPI0->frequency(500000); LPC_SSP0->IMSC = 0; // initially no interrupts requested NVIC_SetVector(SSP0_IRQn,( uint32_t ) spi0_isr); NVIC_ClearPendingIRQ(SSP0_IRQn); NVIC_SetPriority(SSP0_IRQn, 2); NVIC_EnableIRQ(SSP0_IRQn); // SPI1 (using SSP 1 in 1768 chip) mpSPI1 = new SPI(p5, NC, p7); mpSPI1->format(8,0); mpSPI1->frequency(500000); LPC_SSP1->IMSC = 0; // initially no interrupts requested NVIC_SetVector(SSP1_IRQn,( uint32_t ) spi1_isr); NVIC_ClearPendingIRQ(SSP1_IRQn); NVIC_SetPriority(SSP1_IRQn, 2); NVIC_EnableIRQ(SSP1_IRQn); // Resize the string length Resize(length, splitPoint); } ledstrip::~ledstrip() { delete mpLedValuesA; delete mpLedValuesB; } bool ledstrip::Resize(int length, int splitPoint) { if (isr0Busy || isr1Busy) return false; if (mpLedValuesA != NULL) delete mpLedValuesA; if (mpLedValuesB != NULL) delete mpLedValuesB; mLedsBufSize = length*mColoursPerLed; mpLedValuesA = new unsigned char[mLedsBufSize]; mpLedValuesB = new unsigned char[mLedsBufSize]; mpCurLedValues = mpLedValuesA; mLedsInStrip = length; mSplitPoint = splitPoint; Clear(); return true; } void ledstrip::Clear() { /* Timer timr; timr.start(); for (int i = 0; i < mLedsInStrip*mColoursPerLed; i++) mpCurLedValues[i] = 0; timr.stop(); printf("ClearTime loop %d\n", timr.read_us()); // Result is 863uS for 2500 x 3colour LEDS timr.reset(); timr.start(); */ memset(mpCurLedValues, 0, mLedsBufSize); /* timr.stop(); printf("ClearTime memset %d\n", timr.read_us()); // Result is 35uS for 2500 x 3 colour LEDS */ } unsigned char* ledstrip::GetBuffer() { return mpCurLedValues; } int ledstrip::GetBufferSizeinBytes() { return mLedsBufSize; } bool ledstrip::IsBusy() { return isr0Busy || isr1Busy; } void ledstrip::RawFill(int startLed, int numLeds, const unsigned char* pLedVals) { if ((startLed < 0) || (startLed >= mLedsInStrip)) return; if (numLeds >= mLedsInStrip - startLed) numLeds = mLedsInStrip - startLed; int pos = startLed * mColoursPerLed; unsigned char* pBuf = GetBuffer() + pos; memcpy(pBuf, pLedVals, numLeds * mColoursPerLed); } void ledstrip::HsvFill(int startLed, int numLeds, const unsigned char* pLedVals) { if ((startLed < 0) || (startLed >= mLedsInStrip)) return; if (numLeds >= mLedsInStrip - startLed) numLeds = mLedsInStrip - startLed; int pos = startLed * mColoursPerLed; unsigned char* pBuf = GetBuffer() + pos; // Copy over the values converting each to RGB for (int i = 0; i < numLeds; i++) { RgbColor colrVal = HsvToRgb(HsvColor(pLedVals[0],pLedVals[1] & 0xf0, (pLedVals[1] << 4) & 0xf0)); pBuf[pos] = colrVal.r; pBuf[pos+1] = colrVal.g; pBuf[pos+2] = colrVal.b; // printf("HSV %d %d %d RGB %d %d %d\r\n", pLedVals[0],pLedVals[1] & 0xf0, (pLedVals[1] << 4) & 0xf0, colrVal.r, colrVal.g, colrVal.b); pos += mColoursPerLed; pLedVals += 2; } } // Fill - solid colour void ledstrip::Fill(int startLed, int numLeds, int r1, int g1, int b1) { /* Timer timr; timr.start(); */ if ((startLed < 0) || (startLed >= mLedsInStrip)) return; if (numLeds >= mLedsInStrip - startLed) numLeds = mLedsInStrip - startLed; int pos = startLed * mColoursPerLed; unsigned char* pBuf = GetBuffer(); for (int i = 0; i < numLeds; i++) { pBuf[pos] = (unsigned char) r1; pBuf[pos+1] = (unsigned char) g1; pBuf[pos+2] = (unsigned char) b1; pos += mColoursPerLed; } /* timr.stop(); printf("Fill solid %d\n", timr.read_us()); // Fill 50 LEDS solid colour = 11uS */ } // Fill - with interpolation of colours using HSV colour space void ledstrip::Fill(int startLed, int numLeds, int r1, int g1, int b1, int r2, int g2, int b2) { /* Timer timr; timr.start(); */ if ((startLed < 0) || (startLed >= mLedsInStrip)) return; if (numLeds >= mLedsInStrip - startLed) numLeds = mLedsInStrip - startLed; int pos = startLed * mColoursPerLed; RgbColor startRGB(r1,g1,b1); HsvColor startHsv = RgbToHsv(startRGB); RgbColor endRGB(r2,g2,b2); HsvColor endHsv = RgbToHsv(endRGB); int curH = startHsv.h << 16; int curS = startHsv.s << 16; int curV = startHsv.v << 16; int interpSteps = numLeds - 1; if (interpSteps < 1) interpSteps = 1; int incH = ((endHsv.h - startHsv.h) << 16) / interpSteps; int incS = ((endHsv.s - startHsv.s) << 16) / interpSteps; int incV = ((endHsv.v - startHsv.v) << 16) / interpSteps; // Since H is a polar value we need to find out if it is best to go clockwise or anti-clockwise if (endHsv.h > startHsv.h) { if (endHsv.h-startHsv.h > 128) incH = ((startHsv.h-endHsv.h) << 16) / interpSteps; } else { // Go "round the top" using modulo result if (startHsv.h-endHsv.h > 128) incH = ((endHsv.h + 255 - startHsv.h) << 16) / interpSteps; } // printf("StartHSV %d %d %d EndHSV %d %d %d IncHSV %d %d %d\n", startHsv.h, startHsv.s, startHsv.v, endHsv.h, endHsv.s, endHsv.v, incH, incS, incV); unsigned char* pBuf = GetBuffer(); for (int i = 0; i < numLeds; i++) { RgbColor colrVal = HsvToRgb(HsvColor((curH>>16)&0xff,curS>>16,curV>>16)); pBuf[pos] = colrVal.r; pBuf[pos+1] = colrVal.g; pBuf[pos+2] = colrVal.b; // printf("HSV %d %d %d RGB %d %d %d\n", curH>>16, curS>>16, curV>>16, colrVal.r, colrVal.g, colrVal.b); pos += mColoursPerLed; curH = curH + incH; curS = curS + incS; curV = curV + incV; } /* timr.stop(); printf("Fill gradient %d\n", timr.read_us()); // Fill gradient 50 LEDS = 64uS */ } void ledstrip::ShowLeds() { // Check if busy while (isr0Busy || isr1Busy) wait_us(2000); // wait_us(2000); // Set up start points mCurPos0 = 0; mEndPos0 = mSplitPoint*mColoursPerLed; mCurPos1 = mSplitPoint*mColoursPerLed; mEndPos1 = mLedsInStrip*mColoursPerLed; // Set the buffer for the ISRs pLedValues0 = mpCurLedValues; pLedValues1 = mpCurLedValues; // Flip the current buffer to the alternate one for interleaved writing if (mpCurLedValues == mpLedValuesA) { memcpy(mpLedValuesB, mpLedValuesA, mLedsBufSize); mpCurLedValues = mpLedValuesB; } else { memcpy(mpLedValuesA, mpLedValuesB, mLedsBufSize); mpCurLedValues = mpLedValuesA; } // Enable interrupts isr0Busy = true; if (mSplitPoint < mLedsInStrip) isr1Busy = true; // Check if second strip is used LPC_SSP0->IMSC = (1 << SSP_IMSC_TX_RDY) & SSP_IMSC_BITMASK; if (mSplitPoint < mLedsInStrip && mSplitPoint > 0) LPC_SSP1->IMSC = (1 << SSP_IMSC_TX_RDY) & SSP_IMSC_BITMASK; }