16-bit USB I/O

[German_EE]

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?

[Boscoe]

FT600 but it's not simple. Otherwise use a UART bridge with a micro reading your values.

[SiliconWizard]

If you're looking for a ready-made and relatively cheap option: https://numato.com/product/32-channel-usb-gpio-module-with-analog-inputs

[lucazader]

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.

[magic]

Cypress FX2
Chips and cheap breakout boards are available.
A trivial firmware for it and corresponding PC utility: http://lea.hamradio.si/~s57uuu/uuusb/uuusb_software.htm

[asmi]

FT600 but it's not simple.

What's NOT simple about it? What could possibly be more simple than parallel FIFO-style interface?

[rstofer]

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

[KE5FX]

The Cypress FX2 is probably what you want.

[NiHaoMike]

Definitely recommend the FX2. In fact, get at least two so you'll have one to use as a logic analyzer with Sigrok.

[reboots]

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/322196121309

Sigrok's fx2lafw firmware and PC-side software might be a good starting point.

https://sigrok.org/wiki/Fx2lafw

[janoc]

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

[JVR]

16F1459.

You should have USB up and running in a few minutes. It can run a DFU bootloader, and it is tiny.

[PCB.Wiz]

I'm having a lot of trouble finding a 16-bit USB interface.

If 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)

[Brutte]

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.

[amyk]

Definitely recommend the FX2. In fact, get at least two so you'll have one to use as a logic analyzer with Sigrok.

Also known as a "Saleae clone", except that the real Saleae uses only 8 of the 16 channels the FX2 can provide.