uci-mcp/lib/mcp23008-17.js

'use strict'
const Device = require('uci-i2c').Device,
  Port = require('uci-gpio').Port,
  _u = require('uci-utils')

const pSeries = require('p-series');

class MCP23008 extends Device {
  constructor(busObj, i2cAddress, opts) {
      super(busObj, i2cAddress, opts)
        // opts could pass in array of custom pin config, or single for all, or anything
        // this.registers = registers // load in register database
      this.ports = {}
      opts.portID = 'A'
      this.ports.A = new Port(opts)
        // if not specified there RPi is not managing the interrupt
        // pin number on RPi that is connected to and services the interrupt. 4/17/27/22 = 7/11/13/15
      this.ports.A.interPin = opts.interPin
    } // end constructor

  init() {
    console.log('chip ', chip_config.cmd, chipSetByte())
    return this.write(chip_config.cmd, chipSetByte()) // configure chip
      .then(this.writePinsCfg())

  }

  pin(id) { return this.ports.A.pin(id) } // get a reference to a particular pin's object

  // pin configurations should already be set before calling
  writePinsCfg() {
      let jobs = [];
      for (let port in this.ports) {
        for (let setting in registers.pin_config) {
          let reg = registers.pin_config[setting]
          if (port === 'B') { reg = reg + 16 }
          let byte = 0;
          let pins = this.ports[port].allPins
          for (let i = 0; i < 8; i++) {
            let pin = pins[i]
            byte += pin.address.toFmt('DEC') * pin.cfg[setting]
          }
          //		console.log(`port ${port} - setting ${setting} - reg ${reg} -  byte ${byte}`)
          jobs.push(
            () => this.write(reg, byte) // .then((resp)=>console.log(`done writing config ${resp}`))
          )
        }
      }
      return pSeries(jobs)
    } // end writePinsCfg

  pinRead(id, opts) {
      let mcpdev = this;
      return new Promise(function (resolve, reject) {
          let cmd = opts.cmd ? opts.cmd : 'gpio'
          let reg = registers.pin_cmd[cmd]
          let gpio = mcpdev.pin(id, opts.port)
          if (!gpio) {
            reject('no pin found for given id')
          }
          if (gpio.port === 'B') {
            reg = reg + 16
          }
          // call device class read
          console.log('port - reg', gpio.port, reg)
          return mcpdev.read(reg).then(resp => {
            resp = _u.byteFormat(resp, { in: 'DEC',
              out: 'ARY'
            })
            let addr = gpio.pin.address.toFmt('ARY')
            console.log(addr)
            console.log(resp)
            resolve(_u.sum(_u.and(addr, resp))) // resolve 1 or 0
          })
        })
        .then(state => console.log(`pin state ${state}`))
        .catch(err => console.log(err)) // end Promise
    } // end pinRead

} // end 23008
module.exports.MCP23008 = MCP23008

class MCP23017 extends MCP23008 {
  constructor(busObj, i2cAddress, opts) {
    super(busObj, i2cAddress, opts)
      // add a second port

    opts.portID = 'B'
    this.ports.B = new Port(opts)
    this.ports.A.interPin = opts.interPin // if not specified the RPi is not managing the interrupt
  }

  pin(id, port) {
    if (!port) {
      return this.ports.A.pin(id) ? this.ports.A.pin(id) : this.ports.B.pin(id)
    }
    return this.ports[port].pin(id)
  }

} // end MCP23017 Class
module.exports.MCP23017 = MCP23017

/* ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf
 * or see MCP23017.pdf and MCP 23008.pdf in /docs
 * see table 1.5 and details in sections 1.6.x following
 * !!! for 23017 MUST initialize with bit 7 "BANK" of IOCON = 1 for the addresses below
 * then for all registers add 16 (0x10) to each reg address to talk to PortB pins
 * this will make reg addresses be equilvant for 23008 and PortA of 23017
 * reg addresses in the config objects are all in Hexidecminal
 */
// Chip cConfiguration to be used with Register
let chip_config = {
  // byte: ['NULL','INTPOL','ODR','HAEN','DISSLW','SEQOP','MIRROR','BANK']  // see page 18 of 23017 datasheet for 8 setting details
  cmd: 0x0A, // IOCON
  default: {
    val: '10000000', // int pins connected, port A + 0x10 = Port B  -- ignored by 23008
    fmt: 'STR'
  },
  twoints: {
    val: '00000001', // int pins separate, port A + 0x10 = Port B  -- ignored by 23008
    fmt: 'STR'
  }
}

function chipSetByte(setting = 'default') {
  setting = chip_config[setting]
  return _u.byteFormat(setting.val, { in: setting.fmt,
    out: 'DEC'
  })
}
let registers = {
  pin_config: {
    dir: 0,
    ivrt: 1,
    pullup: 6,
    intr: 2,
    usedef: 4,
    defval: 3,
  },
  pin_cmd: {
    intf: 7, // readonly
    intcap: 8, // readonly
    gpio: 9, // read/write
    olat: 10 // read only
  }
}