Required parts and tools<\/h3>\n\n- An Arduino Uno or compatible board.<\/li>\n
- One 74HC595. Siratek product 2402 supplies these as bare 16-pin DIP chips<\/strong>, not on a module.<\/li>\n
- Eight LEDs and eight 220 ohm resistors, to see the output.<\/li>\n
- A breadboard and a good handful of jumper wires.<\/li>\n<\/ul>\n
Handling a bare chip<\/h3>\n
This is probably the first bare integrated circuit in the library, so three things.<\/p>\n
Find pin 1.<\/strong> There is a notch at one end of the package, and sometimes a dot beside pin 1. With the notch at the top, pin 1 is the top left, and the numbers run down the left side and back up the right<\/strong>. Pin 16 is the top right.<\/p>\nStraddle the breadboard\u2019s centre channel.<\/strong> The gap down the middle of a breadboard exists for exactly this. Each row of eight holes on one side is a separate connection from the row opposite, so a chip sitting across the gap has every pin in its own row. Push it in on one side, then the other, gently, and expect the legs to need a slight squeeze inwards first.<\/p>\nPower it properly.<\/strong> Pin 16 to 5 V, pin 8 to ground. A chip with no supply does nothing and gives you no clue why.<\/p>\nThe pins that matter<\/h3>\n
\n\n\nChip pin<\/th>\n Name<\/th>\n What it does<\/th>\n<\/tr>\n<\/thead>\n \n\n14<\/td>\n DS<\/code> or SER<\/code><\/td>\nData in, one bit at a time<\/td>\n<\/tr>\n \n11<\/td>\n SHCP<\/code> or SRCLK<\/code><\/td>\nShift clock: one pulse moves one bit in<\/td>\n<\/tr>\n \n12<\/td>\n STCP<\/code> or RCLK<\/code><\/td>\nLatch clock: one pulse shows all eight at once<\/td>\n<\/tr>\n \n10<\/td>\n MR<\/code> or SRCLR<\/code><\/td>\nClear, active low<\/strong>. Tie to 5 V<\/td>\n<\/tr>\n\n13<\/td>\n OE<\/code><\/td>\nOutput enable, active low<\/strong>. Tie to ground<\/td>\n<\/tr>\n\n9<\/td>\n Q7S<\/code><\/td>\nSerial out, for chaining to the next chip<\/td>\n<\/tr>\n \n15, 1 to 7<\/td>\n Q0<\/code> to Q7<\/code><\/td>\nThe eight outputs<\/td>\n<\/tr>\n \n16<\/td>\n VCC<\/code><\/td>\n5 V<\/td>\n<\/tr>\n \n8<\/td>\n GND<\/code><\/td>\nGround<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\nTwo of those catch people every single time.<\/p>\n
Pin 10 must go to 5 V<\/strong>, not ground. It clears the register when low, so tying it low keeps the chip permanently blank.<\/p>\nPin 13 must go to ground<\/strong>, not 5 V. It disables the outputs when high.<\/p>\nLeave either floating and you get behaviour that changes when you move your hand near the breadboard.<\/p>\n
Note also that Q0<\/code> is pin 15<\/strong>, on its own at the top of one side, while Q1<\/code> to Q7<\/code> are pins 1 to 7 down the other. That is not a mistake in the table.<\/p>\nWhy the latch pin exists<\/h3>\n
The data arrives one bit at a time, so for eight clock pulses the register\u2019s contents are part-old and part-new. If the outputs followed the register directly you would see the bits scrolling across your LEDs on every update.<\/p>\n
The latch is a second set of storage. The outputs show whatever was last latched, and only change when you pulse pin 12. So the sequence is always: latch low, send eight bits, latch high.<\/strong> The change appears in one clean step.<\/p>\nPin reference<\/h2>\n
\n\n\nChip pin<\/th>\n Connect to<\/th>\n Purpose<\/th>\n<\/tr>\n<\/thead>\n \n\n16 VCC<\/code><\/td>\nUno 5V<\/code><\/td>\nPower<\/td>\n<\/tr>\n \n8 GND<\/code><\/td>\nUno GND<\/code><\/td>\nGround<\/td>\n<\/tr>\n \n14 DS<\/code><\/td>\nUno D11<\/code><\/td>\nData<\/td>\n<\/tr>\n \n11 SHCP<\/code><\/td>\nUno D12<\/code><\/td>\nShift clock<\/td>\n<\/tr>\n \n12 STCP<\/code><\/td>\nUno D8<\/code><\/td>\nLatch clock<\/td>\n<\/tr>\n \n10 MR<\/code><\/td>\nUno 5V<\/code><\/td>\nNot clearing<\/td>\n<\/tr>\n \n13 OE<\/code><\/td>\nUno GND<\/code><\/td>\nOutputs enabled<\/td>\n<\/tr>\n \n15, 1 to 7<\/td>\n An LED and a 220 ohm resistor each<\/td>\n The eight outputs<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n![\"A](\"http:\/\/siratek.net\/wp-content\/uploads\/2026\/11\/shift-register-74hc595-wiring.svg\")
Three pins in, eight out. Pin 10 goes high and pin 13 goes low, and both are easy to get backwards.<\/figcaption><\/figure>\nWiring steps<\/h2>\n\n- Unplug the USB cable.<\/li>\n
- Seat the chip across the breadboard\u2019s centre channel, notch to the left, and note where pin 1 is.<\/li>\n
- Pin 16 to the
5V<\/code> rail, pin 8 to the GND<\/code> rail.<\/li>\n- Pin 10 to
5V<\/code>. Pin 13 to GND<\/code>.<\/li>\n- Pin 14 to
D11<\/code>, pin 11 to D12<\/code>, pin 12 to D8<\/code>.<\/li>\n- Put an LED and a 220 ohm resistor from each output to ground. Start with two, prove it works, then add the rest.<\/li>\n
- Plug the USB cable back in.<\/li>\n<\/ol>\n
Step 6 matters. Wiring eight LEDs before testing anything means that when nothing lights you have sixteen new connections to suspect as well as the chip.<\/p>\n
Software and libraries<\/h2>\n
No library is required. shiftOut()<\/code> is part of the Arduino core.<\/p>\nMinimal working example<\/h2>\n\/\/ Siratek: eight outputs from three pins.\n\nconst int dataPin = 11; \/\/ DS, chip pin 14\nconst int clockPin = 12; \/\/ SHCP, chip pin 11\nconst int latchPin = 8; \/\/ STCP, chip pin 12\n\nvoid writeOutputs(byte value) {\n digitalWrite(latchPin, LOW);\n shiftOut(dataPin, clockPin, MSBFIRST, value);\n digitalWrite(latchPin, HIGH);\n}\n\nvoid setup() {\n pinMode(dataPin, OUTPUT);\n pinMode(clockPin, OUTPUT);\n pinMode(latchPin, OUTPUT);\n\n Serial.begin(9600);\n Serial.println(\"Siratek: counting in binary on eight LEDs.\");\n}\n\nvoid loop() {\n for (int i = 0; i < 256; i++) {\n writeOutputs(i);\n delay(200);\n }\n}<\/code><\/pre>\nThat counts from 0 to 255 in binary across the LEDs, which is the clearest possible demonstration that one byte is eight outputs.<\/p>\n
MSBFIRST<\/code> sends the most significant bit first, so bit 7 lands on Q7<\/code>. Use LSBFIRST<\/code> and the pattern appears mirrored. Neither is wrong; pick one and stay with it.<\/p>\nControlling outputs by number<\/h3>\n
Counting in binary is a nice demonstration and an awkward way to say \u201cturn on the third LED\u201d. Bitwise operations fix that.<\/p>\n
\/\/ Siratek: addressing the outputs individually.\n\nconst int dataPin = 11;\nconst int clockPin = 12;\nconst int latchPin = 8;\n\nbyte outputs = 0; \/\/ our own copy of the eight states\n\nvoid writeOutputs() {\n digitalWrite(latchPin, LOW);\n shiftOut(dataPin, clockPin, MSBFIRST, outputs);\n digitalWrite(latchPin, HIGH);\n}\n\nvoid setOutput(int which, bool on) {\n if (on) {\n outputs |= (1 << which); \/\/ set that bit\n } else {\n outputs &= ~(1 << which); \/\/ clear that bit\n }\n writeOutputs();\n}\n\nvoid setup() {\n pinMode(dataPin, OUTPUT);\n pinMode(clockPin, OUTPUT);\n pinMode(latchPin, OUTPUT);\n}\n\nvoid loop() {\n \/\/ a dot running back and forth\n for (int i = 0; i < 8; i++) {\n setOutput(i, true);\n delay(80);\n setOutput(i, false);\n }\n for (int i = 6; i > 0; i--) {\n setOutput(i, true);\n delay(80);\n setOutput(i, false);\n }\n}<\/code><\/pre>\nThe important idea is the outputs<\/code> variable. The chip cannot be read back<\/strong>, so you have to remember what you last sent. Changing one output means changing one bit in your own copy and sending the whole byte again.<\/p>\n1 << which<\/code> builds a byte with a single bit set. |=<\/code> turns that bit on, &= ~<\/code> turns it off, and the rest are untouched. This is worth learning once; it appears in every library that drives hardware.<\/p>\nChaining two chips<\/h3>\n\/\/ Siratek: sixteen outputs, still three pins.\n\nvoid writeSixteen(byte high, byte low) {\n digitalWrite(latchPin, LOW);\n shiftOut(dataPin, clockPin, MSBFIRST, high); \/\/ ends up in the far chip\n shiftOut(dataPin, clockPin, MSBFIRST, low); \/\/ stays in the near one\n digitalWrite(latchPin, HIGH);\n}<\/code><\/pre>\nThe wiring is: pin 9 of the first chip to pin 14 of the second, and the clock and latch lines shared by both. Bits sent first get pushed through the first chip and into the second, which is why the far<\/strong> chip\u2019s byte goes first.<\/p>\nPower both from the same rails, and give each chip a 0.1 microfarad capacitor between its pin 16 and pin 8 if you see flicker.<\/p>\n
Expected result<\/h2>\n
Eight LEDs counting in binary, changing cleanly together with no visible scrolling. If you can see the bits shift across before settling, the latch line is not connected to pin 12.<\/p>\n
Troubleshooting<\/h2>\n
\n\n\nSymptom<\/th>\n Likely cause<\/th>\n Check or fix<\/th>\n<\/tr>\n<\/thead>\n \n\nNothing at all<\/td>\n Pin 10 tied low<\/td>\n It must go to 5V<\/code><\/td>\n<\/tr>\n\nNothing at all, pin 10 fine<\/td>\n Pin 13 tied high<\/td>\n It must go to GND<\/code><\/td>\n<\/tr>\n\nNothing, chip cool<\/td>\n No supply<\/td>\n Pin 16 to 5V<\/code>, pin 8 to GND<\/code><\/td>\n<\/tr>\n\nBits visibly scroll across<\/td>\n Latch not wired, or wrong pin<\/td>\n Pin 12 to the latch pin<\/td>\n<\/tr>\n \nPattern mirrored<\/td>\n Bit order<\/td>\n Swap MSBFIRST<\/code> and LSBFIRST<\/code><\/td>\n<\/tr>\n\nOne output dead<\/td>\n LED backwards, or a bad row<\/td>\n Q0<\/code> is pin 15, not pin 1<\/td>\n<\/tr>\n\nOutputs change when you touch the board<\/td>\n A control pin floating<\/td>\n Check pins 10 and 13<\/td>\n<\/tr>\n \nWorks, then random after adding a second chip<\/td>\n No decoupling<\/td>\n 0.1 uF across each chip\u2019s supply<\/td>\n<\/tr>\n \nLEDs dim with many lit<\/td>\n Total output current<\/td>\n Roughly 70 mA per chip is the ceiling<\/td>\n<\/tr>\n \nChip warm<\/td>\n Too much current drawn<\/td>\n Fewer LEDs, or larger resistors<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\nNext steps<\/h2>\n\n- Easier first:<\/strong> Your First Circuit, an LED and a Resistor<\/em>.<\/li>\n
- Related:<\/strong> Driving a 4-Digit 7-Segment Display<\/em>, which is the obvious thing to put on these outputs.<\/li>\n
- Next project:<\/strong> an LED bar that shows a sensor reading, with no pins used up.<\/li>\n<\/ul>\n
Sources and attribution<\/h2>\n
All text, wiring guidance and code in this tutorial are original Siratek work.<\/p>\n
\n- 74HC595 datasheet for the pin functions, the active-low clear and output-enable behaviour and the output current limits.<\/li>\n
- Arduino core documentation for
shiftOut()<\/code>.<\/li>\n<\/ul>\nSiratek product 2402 supplies the 74HC595 as a bare DIP chip rather than a module, read from the product photographs, which is why this tutorial covers pin numbering and seating a chip on a breadboard. No third-party tutorial text, diagrams, photographs or code has been reproduced here.<\/p>\n
<\/p>\n<\/body>","protected":false},"excerpt":{"rendered":"
A 74HC595 turns three Arduino pins into eight outputs. Chain two and three pins give you sixteen. Chain four and you have thirty-two, still on three pins.<\/p>\n","protected":false},"featured_media":0,"template":"","siratek_tutorial_level":[],"class_list":["post-52352","siratek_tutorial","type-siratek_tutorial","status-publish","hentry"],"yoast_head":"\n
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Handling a bare chip<\/h3>\n
This is probably the first bare integrated circuit in the library, so three things.<\/p>\n
Find pin 1.<\/strong> There is a notch at one end of the package, and sometimes a dot beside pin 1. With the notch at the top, pin 1 is the top left, and the numbers run down the left side and back up the right<\/strong>. Pin 16 is the top right.<\/p>\n Straddle the breadboard\u2019s centre channel.<\/strong> The gap down the middle of a breadboard exists for exactly this. Each row of eight holes on one side is a separate connection from the row opposite, so a chip sitting across the gap has every pin in its own row. Push it in on one side, then the other, gently, and expect the legs to need a slight squeeze inwards first.<\/p>\n Power it properly.<\/strong> Pin 16 to 5 V, pin 8 to ground. A chip with no supply does nothing and gives you no clue why.<\/p>\n Two of those catch people every single time.<\/p>\n Pin 10 must go to 5 V<\/strong>, not ground. It clears the register when low, so tying it low keeps the chip permanently blank.<\/p>\n Pin 13 must go to ground<\/strong>, not 5 V. It disables the outputs when high.<\/p>\n Leave either floating and you get behaviour that changes when you move your hand near the breadboard.<\/p>\n Note also that The data arrives one bit at a time, so for eight clock pulses the register\u2019s contents are part-old and part-new. If the outputs followed the register directly you would see the bits scrolling across your LEDs on every update.<\/p>\n The latch is a second set of storage. The outputs show whatever was last latched, and only change when you pulse pin 12. So the sequence is always: latch low, send eight bits, latch high.<\/strong> The change appears in one clean step.<\/p>\n Step 6 matters. Wiring eight LEDs before testing anything means that when nothing lights you have sixteen new connections to suspect as well as the chip.<\/p>\n No library is required. That counts from 0 to 255 in binary across the LEDs, which is the clearest possible demonstration that one byte is eight outputs.<\/p>\n Counting in binary is a nice demonstration and an awkward way to say \u201cturn on the third LED\u201d. Bitwise operations fix that.<\/p>\n The important idea is the The wiring is: pin 9 of the first chip to pin 14 of the second, and the clock and latch lines shared by both. Bits sent first get pushed through the first chip and into the second, which is why the far<\/strong> chip\u2019s byte goes first.<\/p>\n Power both from the same rails, and give each chip a 0.1 microfarad capacitor between its pin 16 and pin 8 if you see flicker.<\/p>\n Eight LEDs counting in binary, changing cleanly together with no visible scrolling. If you can see the bits shift across before settling, the latch line is not connected to pin 12.<\/p>\n All text, wiring guidance and code in this tutorial are original Siratek work.<\/p>\n Siratek product 2402 supplies the 74HC595 as a bare DIP chip rather than a module, read from the product photographs, which is why this tutorial covers pin numbering and seating a chip on a breadboard. No third-party tutorial text, diagrams, photographs or code has been reproduced here.<\/p>\n <\/p>\n<\/body>","protected":false},"excerpt":{"rendered":" A 74HC595 turns three Arduino pins into eight outputs. Chain two and three pins give you sixteen. Chain four and you have thirty-two, still on three pins.<\/p>\n","protected":false},"featured_media":0,"template":"","siratek_tutorial_level":[],"class_list":["post-52352","siratek_tutorial","type-siratek_tutorial","status-publish","hentry"],"yoast_head":"\nThe pins that matter<\/h3>\n
\n\n
\n \nChip pin<\/th>\n Name<\/th>\n What it does<\/th>\n<\/tr>\n<\/thead>\n \n 14<\/td>\n DS<\/code> or SER<\/code><\/td>\nData in, one bit at a time<\/td>\n<\/tr>\n \n 11<\/td>\n SHCP<\/code> or SRCLK<\/code><\/td>\nShift clock: one pulse moves one bit in<\/td>\n<\/tr>\n \n 12<\/td>\n STCP<\/code> or RCLK<\/code><\/td>\nLatch clock: one pulse shows all eight at once<\/td>\n<\/tr>\n \n 10<\/td>\n MR<\/code> or SRCLR<\/code><\/td>\nClear, active low<\/strong>. Tie to 5 V<\/td>\n<\/tr>\n \n 13<\/td>\n OE<\/code><\/td>\nOutput enable, active low<\/strong>. Tie to ground<\/td>\n<\/tr>\n \n 9<\/td>\n Q7S<\/code><\/td>\nSerial out, for chaining to the next chip<\/td>\n<\/tr>\n \n 15, 1 to 7<\/td>\n Q0<\/code> to Q7<\/code><\/td>\nThe eight outputs<\/td>\n<\/tr>\n \n 16<\/td>\n VCC<\/code><\/td>\n5 V<\/td>\n<\/tr>\n \n 8<\/td>\n GND<\/code><\/td>\nGround<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Q0<\/code> is pin 15<\/strong>, on its own at the top of one side, while Q1<\/code> to Q7<\/code> are pins 1 to 7 down the other. That is not a mistake in the table.<\/p>\nWhy the latch pin exists<\/h3>\n
Pin reference<\/h2>\n
\n\n
\n \nChip pin<\/th>\n Connect to<\/th>\n Purpose<\/th>\n<\/tr>\n<\/thead>\n \n 16 VCC<\/code><\/td>\nUno 5V<\/code><\/td>\nPower<\/td>\n<\/tr>\n \n 8 GND<\/code><\/td>\nUno GND<\/code><\/td>\nGround<\/td>\n<\/tr>\n \n 14 DS<\/code><\/td>\nUno D11<\/code><\/td>\nData<\/td>\n<\/tr>\n \n 11 SHCP<\/code><\/td>\nUno D12<\/code><\/td>\nShift clock<\/td>\n<\/tr>\n \n 12 STCP<\/code><\/td>\nUno D8<\/code><\/td>\nLatch clock<\/td>\n<\/tr>\n \n 10 MR<\/code><\/td>\nUno 5V<\/code><\/td>\nNot clearing<\/td>\n<\/tr>\n \n 13 OE<\/code><\/td>\nUno GND<\/code><\/td>\nOutputs enabled<\/td>\n<\/tr>\n \n 15, 1 to 7<\/td>\n An LED and a 220 ohm resistor each<\/td>\n The eight outputs<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Wiring steps<\/h2>\n
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5V<\/code> rail, pin 8 to the GND<\/code> rail.<\/li>\n5V<\/code>. Pin 13 to GND<\/code>.<\/li>\nD11<\/code>, pin 11 to D12<\/code>, pin 12 to D8<\/code>.<\/li>\nSoftware and libraries<\/h2>\n
shiftOut()<\/code> is part of the Arduino core.<\/p>\nMinimal working example<\/h2>\n
\/\/ Siratek: eight outputs from three pins.\n\nconst int dataPin = 11; \/\/ DS, chip pin 14\nconst int clockPin = 12; \/\/ SHCP, chip pin 11\nconst int latchPin = 8; \/\/ STCP, chip pin 12\n\nvoid writeOutputs(byte value) {\n digitalWrite(latchPin, LOW);\n shiftOut(dataPin, clockPin, MSBFIRST, value);\n digitalWrite(latchPin, HIGH);\n}\n\nvoid setup() {\n pinMode(dataPin, OUTPUT);\n pinMode(clockPin, OUTPUT);\n pinMode(latchPin, OUTPUT);\n\n Serial.begin(9600);\n Serial.println(\"Siratek: counting in binary on eight LEDs.\");\n}\n\nvoid loop() {\n for (int i = 0; i < 256; i++) {\n writeOutputs(i);\n delay(200);\n }\n}<\/code><\/pre>\nMSBFIRST<\/code> sends the most significant bit first, so bit 7 lands on Q7<\/code>. Use LSBFIRST<\/code> and the pattern appears mirrored. Neither is wrong; pick one and stay with it.<\/p>\nControlling outputs by number<\/h3>\n
\/\/ Siratek: addressing the outputs individually.\n\nconst int dataPin = 11;\nconst int clockPin = 12;\nconst int latchPin = 8;\n\nbyte outputs = 0; \/\/ our own copy of the eight states\n\nvoid writeOutputs() {\n digitalWrite(latchPin, LOW);\n shiftOut(dataPin, clockPin, MSBFIRST, outputs);\n digitalWrite(latchPin, HIGH);\n}\n\nvoid setOutput(int which, bool on) {\n if (on) {\n outputs |= (1 << which); \/\/ set that bit\n } else {\n outputs &= ~(1 << which); \/\/ clear that bit\n }\n writeOutputs();\n}\n\nvoid setup() {\n pinMode(dataPin, OUTPUT);\n pinMode(clockPin, OUTPUT);\n pinMode(latchPin, OUTPUT);\n}\n\nvoid loop() {\n \/\/ a dot running back and forth\n for (int i = 0; i < 8; i++) {\n setOutput(i, true);\n delay(80);\n setOutput(i, false);\n }\n for (int i = 6; i > 0; i--) {\n setOutput(i, true);\n delay(80);\n setOutput(i, false);\n }\n}<\/code><\/pre>\noutputs<\/code> variable. The chip cannot be read back<\/strong>, so you have to remember what you last sent. Changing one output means changing one bit in your own copy and sending the whole byte again.<\/p>\n1 << which<\/code> builds a byte with a single bit set. |=<\/code> turns that bit on, &= ~<\/code> turns it off, and the rest are untouched. This is worth learning once; it appears in every library that drives hardware.<\/p>\nChaining two chips<\/h3>\n
\/\/ Siratek: sixteen outputs, still three pins.\n\nvoid writeSixteen(byte high, byte low) {\n digitalWrite(latchPin, LOW);\n shiftOut(dataPin, clockPin, MSBFIRST, high); \/\/ ends up in the far chip\n shiftOut(dataPin, clockPin, MSBFIRST, low); \/\/ stays in the near one\n digitalWrite(latchPin, HIGH);\n}<\/code><\/pre>\nExpected result<\/h2>\n
Troubleshooting<\/h2>\n
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\n \nSymptom<\/th>\n Likely cause<\/th>\n Check or fix<\/th>\n<\/tr>\n<\/thead>\n \n Nothing at all<\/td>\n Pin 10 tied low<\/td>\n It must go to 5V<\/code><\/td>\n<\/tr>\n\n Nothing at all, pin 10 fine<\/td>\n Pin 13 tied high<\/td>\n It must go to GND<\/code><\/td>\n<\/tr>\n\n Nothing, chip cool<\/td>\n No supply<\/td>\n Pin 16 to 5V<\/code>, pin 8 to GND<\/code><\/td>\n<\/tr>\n\n Bits visibly scroll across<\/td>\n Latch not wired, or wrong pin<\/td>\n Pin 12 to the latch pin<\/td>\n<\/tr>\n \n Pattern mirrored<\/td>\n Bit order<\/td>\n Swap MSBFIRST<\/code> and LSBFIRST<\/code><\/td>\n<\/tr>\n\n One output dead<\/td>\n LED backwards, or a bad row<\/td>\n Q0<\/code> is pin 15, not pin 1<\/td>\n<\/tr>\n\n Outputs change when you touch the board<\/td>\n A control pin floating<\/td>\n Check pins 10 and 13<\/td>\n<\/tr>\n \n Works, then random after adding a second chip<\/td>\n No decoupling<\/td>\n 0.1 uF across each chip\u2019s supply<\/td>\n<\/tr>\n \n LEDs dim with many lit<\/td>\n Total output current<\/td>\n Roughly 70 mA per chip is the ceiling<\/td>\n<\/tr>\n \n Chip warm<\/td>\n Too much current drawn<\/td>\n Fewer LEDs, or larger resistors<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n Next steps<\/h2>\n
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Sources and attribution<\/h2>\n
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shiftOut()<\/code>.<\/li>\n<\/ul>\n