Shift out using SPI doesn't work.

actually, questioned on arduino stackexchange,
but got nothing i'm asking again ;-(


i made sample using 2 74hc595 on arduino uno.
so did this:

(there isn't resistor on image, there 220ohm resistor on every leds.)
and uploaded code.

code: [select]

//1.6us+62.5ns
#include <spi.h>

#define sbi(port, bit) (port) |= (1 << (bit))
#define cbi(port, bit) (port) &= ~(1 << (bit))

int latchpin = 12;
int clockpin = 13;
int datapin = 11;

byte data[]={ 0b10101010,0b11001100 };

void _595_out() {
    cbi(portb, 4);
    spi.transfer(data[0] );
    spi.transfer( data[1] );
    sbi(portb, 4);
}

void setup() {
    pinmode(latchpin, output);
    pinmode(clockpin, output);
    pinmode(datapin, output);

    spi.setclockdivider(spi_clock_div2);
    spi.setbitorder(msbfirst);
    spi.setdatamode(spi_mode0);
    spi.begin();
}

void loop() {
    _595_out();
}
and worked expected. but, when changed sketch this,

code: [select]

//1.6us+62.5ns
#include <spi.h>

#define sbi(port, bit) (port) |= (1 << (bit))
#define cbi(port, bit) (port) &= ~(1 << (bit))
#define chipno 2
int latchpin = 12;
int clockpin = 13;
int datapin = 11;

byte data[]={ 0b10101010,0b11001100 };

void _595_out() {
    cbi(portb, 4);
    spi.transfer(data[0]);
    spi.transfer(data[1]);
    sbi(portb, 4);
}

void setup() {
    pinmode(latchpin, output);
    pinmode(clockpin, output);
    pinmode(datapin, output);

    spi.setclockdivider(spi_clock_div2);
    spi.setbitorder(msbfirst);
    spi.setdatamode(spi_mode0);
    spi.begin();
    serial.begin(9600);
}

void loop() {
    for(unsigned int z = 0; z < 65535; z++) {
        data[0] = z & 255;
        data[1] = (z & 65280) >> 8;
        serial.println("a");
        serial.print(data[0]);
        serial.print("/");
        serial.println(data[1]);
        serial.println("b");
        _595_out();
        serial.println("c");
        delay(500);
    }
}
74hc595s aren't working. leds aren't on.
printing serial works well. 74hc595s aren't working.
and removing serial-related thing doesn't solved problem.
where did wrong?

quote from: musoftware on jan 13, 2017, 03:53 pm

and uploaded code.

code: [select]

int latchpin = 12;
int clockpin = 13;
int datapin = 11;
where did wrong?

you can't use miso pin slaveselect (latch) pin.  try using pin 10 default slaveselect spi.

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