FT232H

WebUSB based driver for FT232H chip

Intended to provide I²C abstraction for compatibility with I2CBus

Example

Standard setup

import { FT232H, BIT_MODE } from '@johntalton/ft232h'

const usbDevice = // via navigator.usb.requestDevice

// open usb
await usbDevice.open()

// chip form usb device
const ftDevice = await FT232H.from(usbDevice)

// using MPSSE
await ftDevice.setBitMode(BIT_MODE.MPSSE)

Blink LED via GPIO

import { PIN_STATE_COMMANDS } from '@johntalton/ft232h'

// ...
export const delayMs = ms => new Promise(resolve => setTimeout(resolve, ms))

// LED on
await ftDevice.sendData(Uint8Array.from([
  PIN_STATE_COMMANDS.SET_DATA_BITS_HIGH_BYTE,
  0b1000_0000, // gpio to set (HIGH)
  0b1000_0000
]))

await delayMs(500)

// LED off
await ftDevice.sendData(Uint8Array.from([
  PIN_STATE_COMMANDS.SET_DATA_BITS_HIGH_BYTE,
  0b0000_0000, // gpio to set (LOW)
  0b1000_0000  // direction (output)
]))

Using it as a I²C bus

import { FT232HBus } from '@johntalton/ft232h'
import { I2CAddressedBus } from '@johntalton/and-other-delights'
import { ADT7410 } from '@johntalton/adt7410'

// ...

// init sets the chip into mode compatible for I2C communication
// this is required prior to any I2C interactions
// any other command that alter the chips configuration will
// invalidate the bus
await FT232HBus.init(ftDevice)
const bus = new FT232HBus(ftDevice)

// but can now be used as part of any I2CBus sensor
// following example for ADT7410
const DEFAULT_ADDR = 0x48
const sensor = ADT7410.from(new I2CAddressedBus(DEFAULT_ADDR, bus))

// get temperature
const { temperatureC } = await sensor.getTemperature()