Проблема с Raspberry Pi 3 B +, ONOFF (Node) и Sparkfun Large Digit Driver

Question

Я не могу получить прикрепленный код Javascript для правильного управления моим 7-сегментным драйвером больших цифр от Sparkfun. Однако почти идентичный код в Python прекрасно работает. Похоже, это должно быть как-то связано с тем, как библиотека GPIO (onoff) в Node управляет портами GPIO, потому что изменение настроек меняет поведение, но не успешно.

// GUIDE FOR RASPBERRY PI
// https://medium.com/@jonah.lefkoff/how-to-hook-up-the-sparkfun-7-segment-display-to-a-raspberry-pi-577591ba94b5


console.log("STARTING CLOCK")

// Ability to shut down
const child_process = require("child_process")
process.on('SIGINT', () => {
    clock.unexport()
    latch.unexport()
    data.unexport()
})

// Load GPIO library onoff
let GPIO = require('onoff').Gpio

// Number of display digits that are physically wired up
const DIGITS = 1


// Set everything to LOW
let latch = new GPIO(17, 'low', 'rising', { activeLow: false })
let clock = new GPIO(27, 'low', 'rising', { activeLow: false })
let data = new GPIO(22, 'low', 'rising', { activeLow: false })


function postNumber(num, decimal) {
    let a = 1 << 0
    let b = 1 << 6
    let c = 1 << 5
    let d = 1 << 4
    let e = 1 << 3
    let f = 1 << 1
    let g = 1 << 2
    let dp = 1 << 7
    let segments

    switch (num) {
        case 1: segments = b | c; break;
        case 2: segments = a | b | d | e | g; break;
        case 3: segments = a | b | c | d | g; break;
        case 4: segments = b | c | f | g; break;
        case 5: segments = a | c | d | f | g; break;
        case 6: segments = a | c | d | e | f | g; break;
        case 7: segments = a | b | c; break;
        case 8: segments = a | b | c | d | e | f | g; break;
        case 9: segments = a | b | c | d | f | g; break;
        case 0: segments = a | b | c | d | e | f; break;
        case 'c': segments = d | e | g; break;
        case '-': segments = g; break;
        case ' ': segments = 0; break;
        default: segments = 0; break;
    }

    //if (decimal) segments = segments | dp

    console.log(num, segments.toString(2), segments)

    for (let y = 0; y < 8; y++) {
        clock.writeSync(GPIO.LOW)
        data.writeSync(segments & 1 << (7 - y))
        clock.writeSync(GPIO.HIGH)
    }

}



function showNumber(val) {
    let num = Math.abs(val) // remove any signs
    for (let x = 1; x <= DIGITS; x++) {
        let remainder = parseInt(num % 10) //the remainder is what needs to be posted to each digit
        postNumber(remainder, false)
        num /= 10
    }

    latch.writeSync(GPIO.LOW)
    latch.writeSync(GPIO.HIGH)
}


for (let x = 0; x < 10; x++) {
    showNumber(x)
    child_process.execSync("sleep .5")
}

FWIW, работает следующий код Python:

#!/usr/bin/env python
#By Jonah
import RPi.GPIO as GPIO
import time
from time import sleep
GPIO.setmode(GPIO.BOARD)
segmentLatch=11
segmentClock=13
segmentData=15
GPIO.setup(segmentClock,GPIO.OUT)
GPIO.setup(segmentData,GPIO.OUT)
GPIO.setup(segmentLatch,GPIO.OUT)
GPIO.output(segmentClock,GPIO.LOW)
GPIO.output(segmentData,GPIO.LOW)
GPIO.output(segmentLatch,GPIO.LOW)
number=0
DIGITS = 1
#Takes a number and displays 2 numbers. Display absolute value (no negatives)
#look here maybe bug between value+number
def showNumber(value):
        number = abs(value) #Remove negative signs and any decimals
        x=0
        while(x < DIGITS):
                remainder=number % 10
                postNumber(remainder)
                number /= 10
                x += 1
#Latch the current segment data
        GPIO.output(segmentLatch,GPIO.LOW)
        GPIO.output(segmentLatch,GPIO.HIGH) #Register moves storage register on the rising edge of RCK
#Given a number, or - shifts it out to the display
def postNumber(number):
    a=1<<0
    b=1<<6
    c=1<<5
    d=1<<4
    e=1<<3
    f=1<<1
    g=1<<2
    dp=1<<7

    if   number == 1: segments =     b | c
    elif number == 2: segments = a | b |     d | e |     g
    elif number == 3: segments = a | b | c | d |         g
    elif number == 4: segments =     b | c |         f | g
    elif number == 5: segments = a |     c | d     | f | g
    elif number == 6: segments = a |     c | d | e | f | g
    elif number == 7: segments = a | b | c
    elif number == 8: segments = a | b | c | d | e | f | g
    elif number == 9: segments = a | b | c | d     | f | g
    elif number == 0: segments = a | b | c | d | e | f
    elif number == ' ': segments = 0
    elif number == 'c': segments = g | e | d
    elif number == '-': segments = g
    else : segments = False

    #if (segments != dp):
    print (number, "{0:b}".format(segments), segments)

    y=0
    while(y<8):
        GPIO.output(segmentClock,GPIO.LOW)
        GPIO.output(segmentData,segments & 1 << (7-y))
        GPIO.output(segmentClock,GPIO.HIGH)
        y += 1

x=0
while(x < 10):
        showNumber(x)
        x += 1
        sleep(0.2)

GPIO.cleanup()

Answer 1

Я понял, но пока не совсем понял ...

С библиотекой Javascript (onoff) биты сдвигаются в том же порядке. Тем не менее, они регистрируются в обратном направлении. Решение состояло в том, чтобы изменить код, чтобы изменить порядок битов, сдвигаемых в регистр перед фиксацией. Вот рабочий код javascript ...

// GUIDE FOR RASPBERRY PI
// https://medium.com/@jonah.lefkoff/how-to-hook-up-the-sparkfun-7-segment-display-to-a-raspberry-pi-577591ba94b5


console.log("STARTING CLOCK")

// Ability to shut down
const child_process = require("child_process")
process.on('SIGINT', () => {
    clock.unexport()
    latch.unexport()
    data.unexport()
})

// Load GPIO library onoff
let GPIO = require('onoff').Gpio

// Number of display digits that are physically wired up
const DIGITS = 1


// Set everything to LOW
let latch = new GPIO(17, 'out')
let clock = new GPIO(27, 'out')
let data = new GPIO(22, 'out')


function postNumber(num, decimal) {
    let a = 1 << 0 //00000001
    let b = 1 << 6 //01000000
    let c = 1 << 5 //00100000
    let d = 1 << 4 //00010000
    let e = 1 << 3 //00001000
    let f = 1 << 1 //00000010
    let g = 1 << 2 //00000100
    let p = 1 << 7 //10000000
    let segments = false

    switch (num) {
        case 1: segments = b | c; break;
        case 2: segments = a | b | d | e | g; break;
        case 3: segments = a | b | c | d | g; break;
        case 4: segments = b | c | f | g; break;
        case 5: segments = a | c | d | f | g; break;
        case 6: segments = a | c | d | e | f | g; break;
        case 7: segments = a | b | c; break;
        case 8: segments = a | b | c | d | e | f | g; break;
        case 9: segments = a | b | c | d | f | g; break;
        case 0: segments = a | b | c | d | e | f; break;
        default: break;
    }

    console.log('segments', segments, segments.toString(2))

    //if (decimal) segments = segments | p

    latch.writeSync(GPIO.LOW)
    for (let y = 8; y > 0; y--) {
        let shift = (segments >> y - 1) & 1
        clock.writeSync(GPIO.LOW)
        data.writeSync(shift)
        console.log('shift', shift)
        clock.writeSync(GPIO.HIGH)
    }
    latch.writeSync(GPIO.HIGH)

}



function showNumber(val) {
    let num = Math.abs(val) // remove any signs
    for (let x = 1; x <= DIGITS; x++) {
        let remainder = parseInt(num % 10) //the remainder is what needs to be posted to each digit
        postNumber(remainder, false)
        num /= 10
    }
}

for (let x = 0; x < 10; x++) {
    showNumber(x)
    child_process.execSync("sleep .1")
}