8-bit ADC into USB port ?

[aljamri]

Hi everybody, I've did easy PIC connection I/O s into PC using parallel port, and seen NG PIC tutorial Seven RS232, but now having a project to supply ADC 8bit output into PC, so thinking to us USB port if possible (just thinking loudly).
Is this possible? and what is required?
a USB support PIC, or special module to interface?

 

[Nigel Goodwin]

Use a serial/USB converter 'lead', it's the cheapest and easiest way.

 

[be80be]

aljamri USB is a big bunch of code and starts in C18 for the pic MikroC C has USB hid

I would go with Nigel

Use a serial/USB converter 'lead', it's the cheapest and easiest way.

But if you like C18 there a lot of code samples to read up on But you'll end of having to Buy C18

 

[aljamri]

Use a serial/USB converter 'lead', it's the cheapest and easiest way.

aljamri USB is a big bunch of code and starts in C18 for the pic MikroC C has USB hid

I would go with Nigel

But if you like C18 there a lot of code samples to read up on But you'll end of having to Buy C18

In this cas my ADC output has to be serial not parallel, right ?

 

[be80be]

Yes you want serial

 

[aljamri]

I'm not sure about this but searched my Farnell online and found:

serial/USB converter 'lead' like This ?
and here is its Manual .

 

[Nigel Goodwin]

In this cas my ADC output has to be serial not parallel, right ?

I presumed you were using a PIC for the ADC, so you just send the data out from it as RS232, as per my tutorials.

It would seem pretty pointless buying a MUCH more expensive (and lower spec) ADC, then adding a processor to read it and send the data out as serial.

 

[Nigel Goodwin]

I'm not sure about this but searched my Farnell online and found:

serial/USB converter 'lead' like This ?
and here is its Manual .

That's the kind of thing, but they were under £1 on Amazon when I bought mine, although they are £3 odd now.

https://www.amazon.co.uk/exec/obidos/ASIN/B00077DJIQ/ref=ox_ya_os_product

 

[Reloadron]

but now having a project to supply ADC 8bit output into PC, so thinking to us USB port if possible

What exactly are you doing? Meaning what is the analog signal you are working with?

Ron

 

[aljamri]

As a matter of fact, this is my workmate project, he is dealing with electrical side of our firm. He thought of a type of Data Logger for the power variations in substations, so that he put a simple block diagram and distribute each task to the concern department ( see attachment ).
My part is to receive the 5vdc output and deliver it to the PC only. He suggested using ADC IC, but as you know, parallel port is not famous for today’s LapTops, and even the RS232, which made USB is the preferred connection.
Know you suggested to use serial/USB converter lead , the PIC as ADC and Nigel’s RS232 board to connect them, which makes it much easier and approachable.
Thanks for all.

 

[AtomSoft]

There is a FIFO to USB which should allow Parallel from FTDI

 

[Reloadron]

Hi Ya aljamri

Actually I agree as to the use of the old parallel port and RS232 ports. They are going away unless one specifically hunts down a system designed with them included. I have also used USB to RS232 converters but actually think today's new systems being developed should be USB based or similar (like the wireless systems and ethernet). Anyway, looking at what you have before you. There are plenty of inexpensive hardware USB solutions out there.

I have used these very inexpensive devices (actually earlier versions) and looked at several of these devices. The DATAQ DI 145 starter kit at about $29 USD for example gives you 4 differential analog input channels of +/- 10 volts. That being with 10 bit aquisition. They were also offering 12 bit units? Don't know where those went. The nice thing is the basic included software which allows easy data recording and storage for later review. They are also very easy to write your own software for.

So looking at your drawing. I see a 50/5 CT so we get 0 to 50 amps is equal to 0 to 5 amps. I would then run that CT output in a loop through something like this. You now have 0 to 50 amps is equal to 0 to 10 volts, 0 to 5 volts. 4 to 20 mA or just about anything you want for scaling.

The products I mention are just examples and for the better part are pretty common items globally available. I believe I have some pictures on my home computer of some of those items that are set up and configured. In addition to line current(s) it also becomes easy to measure line voltages and plot them with current.

In conclusion I obviously lean towards USB interfaced devices and for the reasons I mentioned.

Ron

 

[aljamri]

That's the kind of thing, but they were under £1 on Amazon when I bought mine, although they are £3 odd now.

https://www.amazon.co.uk/exec/obidos/ASIN/B00077DJIQ/ref=ox_ya_os_product

I've paced an order for two peices, and for my surprise, they agreed to bring it to my country with only additional 7 pounds.

Thanks Nigle

 

[aljamri]

There is a FIFO to USB which should allow Parallel from FTDI

Thanks Jason, but what is FIFO ? is this to do anything with (First In First Out)

 

[Mikebits]

You can buy this already made for less money than it would take to build and develop your own.
https://labjack.com/products?gclid=CP6Wo_rMpKoCFRNjgwodt0XcVQ

 

[AtomSoft]

Thanks Jason, but what is FIFO ? is this to do anything with (First In First Out)

Yeah here is a link:

https://www.ftdichip.com/Products/ICs/FT245R.htm

he FT245R is the latest device to be added to FTDI’s range of USB FIFO interface Integrated Circuit Devices. The FT245R is a USB to parallel FIFO interface, with the new FTDIChip-ID™ security dongle feature.

Single chip USB to parallel FIFO bidirectional data transfer interface.

I think this is a good option if you dont want to use serial and need parallel and USB

 

[Mikebits]

Since this is work related, one must consider the cost of design your own vs. buy off the shelf.

Let's break it down.

• Off the shelf ~ $100.00

Design your own.

• Research parts: Hours spent x your salary
• Schematic design: ~40-80 hrs x your salary
• Order parts: Your time plus purchaser time
• Design PCB: Hours spent x PCB designer salary
• Fabricate PCB: $???
• Assemble board: Assembly time and cost
• Debug design: $???
• Rework errors
• Software development...

So you see, at the end of the day, it may be more economical to buy off the shelf.

 

[AtomSoft]

Well if it cost more to design it at least you know the final build will be cheaper and easily replaceable. Dont have to worry about stock or other company holding you back if your building it. Also you will be more familiar with it if something goes wrong

 

[Reloadron]

Since this is work related, one must consider the cost of design your own vs. buy off the shelf.

Let's break it down.

• Off the shelf ~ $100.00

Design your own.

• Research parts: Hours spent x your salary
• Schematic design: ~40-80 hrs x your salary
• Order parts: Your time plus purchaser time
• Design PCB: Hours spent x PCB designer salary
• Fabricate PCB: $???
• Assemble board: Assembly time and cost
• Debug design: $???
• Rework errors
• Software development...

So you see, at the end of the day, it may be more economical to buy off the shelf.

I agree and linked to a data acquisition simple 4 channel device with isolated differential channels that runs about $30 US. That includes some really nice logging software and additionally like Mike's suggestion is very easy to roll your own software for. However, it is an off the shelf solution that is also USB.

When I present something I have to do exactly what Mike mentions and unless there is a considerable savings with DIY we buy off the shelf. My billing rate for engineering time exceeds $200 USD an hour.

Ron

 

[AtomSoft]

I need to live where you are... $200 a hr. i would be rich.. $30 isnt bad but for something so simple $200 for 1 product is overkill