16-bit USB I/O - Page 1
Forum section: electronics / general

author: German_EE
author_rank: Super Contributor
timestamp: April 01, 2019, 05:48:12 pm
content: This post has been placed in the microcontroller section on purpose as the answer will probably be a custom programmed chip.I have a need to transfer 4 x 16-bit words from some 74HC based counters to a PC and this needs to be done over a USB port. Once in the PC the four words will be assembled into two 32-bit words and some math performed.However................I'm having a lot of trouble finding a 16-bit USB interface. Lots of people sell eight bit USB expanders and one is selling a twelve bit unit but using either of these will increase the chip count significantly. Does anyone know of a company that sells a 16-bit wide USB interface with either TTL or CMOS inputs?

author: Boscoe
author_rank: Frequent Contributor
timestamp: April 01, 2019, 06:02:15 pm
content: FT600 but it's not simple. Otherwise use a UART bridge with a micro reading your values.

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 01, 2019, 06:05:00 pm
content: If you're looking for a ready-made and relatively cheap option:https://numato.com/product/32-channel-usb-gpio-module-with-analog-inputs

author: lucazader
author_rank: Regular Contributor
timestamp: April 01, 2019, 06:29:41 pm
content: If you are looking for more of a mass production part, then a microcontroller might be best.Quite simple to pick up an ARM based micro with USB (say STM32F042) program it as a USB CDC device (virtual com port). and then just read in the data required on the pins of the micro.But only go this route if you need more of a production ready option.

author: magic
author_rank: Super Contributor
timestamp: April 01, 2019, 07:32:38 pm
content: Cypress FX2Chips and cheap breakout boards are available.A trivial firmware for it and corresponding PC utility:http://lea.hamradio.si/~s57uuu/uuusb/uuusb_software.htm

author: asmi
author_rank: Super Contributor
timestamp: April 01, 2019, 08:12:47 pm
content: Quote from: Boscoe on April 01, 2019, 06:02:15 pmWhat's NOT simple about it? What could possibly be more simple than parallel FIFO-style interface?

author: rstofer
author_rank: Super Contributor
timestamp: April 01, 2019, 09:41:53 pm
content: A USB HID Device is made for this kind of low volume transfer. I used it in a uC to transfer knobs, switches and dials to Microsoft Flight Simulator. The standard packet is 64 bytes and you can use the bits anyway you want.I used RAWHID on a Teensy from PJRC. I think I also used a Microchip board from Digilent but it's been a long time.https://www.pjrc.com/teensy/rawhid.html

author: KE5FX
author_rank: Super Contributor
timestamp: April 01, 2019, 10:22:03 pm
content: The Cypress FX2 is probably what you want.

author: NiHaoMike
author_rank: Super Contributor
timestamp: April 02, 2019, 01:37:59 am
content: Definitely recommend the FX2. In fact, get at least two so you'll have one to use as a logic analyzer with Sigrok.

author: reboots
author_rank: Regular Contributor
timestamp: April 03, 2019, 03:49:38 pm
content: Fourthing(?) Cypress FX2. Here's a cheap and widely available development board which exposes 16 I/O:https://www.ebay.com/itm/NEW-EZ-USB-FX2LP-Cypress-CY7C68013A-USB2-0-Developement-Board/322196121309Sigrok's fx2lafw firmware and PC-side software might be a good starting point.https://sigrok.org/wiki/Fx2lafw

author: janoc
author_rank: Super Contributor
timestamp: April 03, 2019, 06:44:34 pm
content: FTDI's FT232H, these can be configured to SPI mode. Then just use two 8 bit shift registers to interface your logic. Dongles and breakouts with FT232 can be found cheaply, e.g.https://learn.adafruit.com/adafruit-ft232h-breakout/spi

author: JVR
author_rank: Regular Contributor
timestamp: April 12, 2019, 02:34:33 pm
content: 16F1459.You should have USB up and running in a few minutes. It can run a DFU bootloader, and it is tiny.

author: PCB.Wiz
author_rank: Super Contributor
timestamp: April 12, 2019, 07:47:52 pm
content: Quote from: German_EE on April 01, 2019, 05:48:12 pmIf you need speed, the FX2 mentioned above is fast, and has low cost modules.If you need lowest price for volumes, then a small MCU is better.PIC16F1459 mentioned above is Microchip 8b offering.Similar, but cheaper are SiLabs EFM8UB1 (64c/3k) or EFM8UB3 (93c/3k)

author: Brutte
author_rank: Frequent Contributor
timestamp: April 13, 2019, 02:09:07 am
content: We do not know the speed, the latch to latch 64 bits and of course the quantity. If that is just for test and the signal is ms range then I would just buy several FT232R cables (these chips have parallel 8-bit interface). Or several eBay logic analyzers.If that is for mass production then that is a different story.

author: amyk
author_rank: Super Contributor
timestamp: April 13, 2019, 02:58:48 am
content: Quote from: NiHaoMike on April 02, 2019, 01:37:59 amAlso known as a "Saleae clone", except that the real Saleae uses only 8 of the 16 channels the FX2 can provide.