MCU + USB

You missed out the most important critera to answer your question. How many units are you going to sell? How fast do you need to get it to the market place? What percentage of the final unit cost does the USB costs represent?

I uyse the cypress FX series of 8051/USB devices. FX2LP.. They give you the driver and the api. It does work. I have three products using it right now. Not _that_ hard to get up and running but not a simple task either. I chose not to go the FTDI route because in the end.. it would have simply been a slow serial interface. After the initial learning curve I can now implement USB anywhere.

I believe the cypress parts are actually cheaper than the FTDI part.

YOu can also get a little FX2 Usb development board from bitwise systems. google it.

I would gladly accept some learning curve. I do like challenges, but I would prefer taking them with a core newer than the 8051.

Yes, and so are some 8-bit (e.g. Freescale 908JBx) and 32-bit (e.g. Philips LPC214x) MCUs. I specially like the LPC214x option because those MCUs are cheap, powerful, and already include the other peripherals I mentioned I need. If someone tells me that Philips provides similar tools to develop the USB driver, I could go for option 1.

Is there anything similar to

but for ARM7 LPC214x devices?

Also, is it true that if I go for option 1 I need to buy a (USB) vendor ID, and that this is expensive?

the

now.

chose

implement

4 clock/48Mhz device. Pretty quick for most things.

NOt necessarily. I am not sure what you are doing but a Vendor ID is $1500. Although you can run with the Cypress VID using their driver.. or you can fake your own for in-house use.

I'm using the PIC18F2455 for a USB interface. It's available in DIL, which makes it easy for prototyping, and includes the transceivers. I'm designing the PCB, so I won't know how easy or difficult it is until I have the prototype hardware working.

Leon

SiLabs C8051F320 have FLASH + USB, and Atmel AT89C513x series have Flash/USB, but are light on the ADCs. Cypress have a number of choices, with good maturity.

.. but if the F232R WILL do all you need, without development times, you need to look at the volumes carefully to justify using something else. ( and then, FTDI caim $1.80/10K)

-jg

I should add the ST uPSD34xx series, with full speed USB, and Maxim have an interesting SPIUSB device, the MAX3420, if you want serial (low pin count), but faster than FT232R.

-jg

Lookup the "Communication device class" (or just CDC) on usb.org. This provides a standard way of providing a virtual COM port that is supported by Win98 onwards. No Windows side programming is required.

If you take a look at the SAM7X lwIP demo application in the FreeRTOS.org download (link below) you will find some sample source code. When you connect the USB to Windows it registers as a normal COM port so can be accessed just like a 232 port.

Regards, Richard.

Yes, I'm having a headache about this.

I'm curious. Where did you read that price? The WebShop at the FTDI page sells the FT232RL for 3.83 EUR, in units, but doesn't say any other price for larger volumes.

Sorry, it does say: US$4.5000/pc, in units. US$3.6024/pc, for 100 pcs.

Google on [FT232R price ], and near the top is

You should also look at the ARM SAM7 CPUs from Atmel.

The USB ARM CPUs (LPC214? and SAM7) are very different from the

8051 based EZusb/FX2. In fact, they are so different, that you shouldn't even be considering them as alternatives for the same application.

The ARM chips are much more powerful CPUs, but they are only full-speed USB (12mbps) capable. The EZusb/FX2 is high-speed USB (480mbps), 40 times the bandwidth. The 8051 core is not a limitation, because the chip has integrated high speed FIFOs, and a programable interface, so the 8051 just sets everything up, and then gets out of the way. The data then moves between the GPIF, FIFOs and USB with no CPU intervention.

So if your application is very data intensive, with little need for computing power on the client end, the EZusb/FX2 is a good choice.

If your data bandwidth needs are more modest, but you want some CPU horsepower, or the convenience of a high level language, then the ARM CPUs (LPC214? or SAM7) would be good choices.

There is an active Yahoo group for LPC2???:

Engineers from Philips participate in the group regularly.

Don't know. I am not a Windows guy. My desktop is running FreeBSD, so instead of going to jungo.com and paying $3000, I just type "cd /usr/ports/misc/ezload; make install".