BlackFin USB

I recently had a similar problem with a USB controller from Renesas (nee NEC) - the data I had said nothing about the use of a pin called "RREF". I ended up purchasing a commercial product that used that part (for about $20 from a computer store), and traced that part of the circuit.

It had a 1.6 k ohm resistor to ground.

Later, after NDAs were signed and I had the real datasheet, I discovered that it was used for setting the reference current used for various things, IIRC including PLL bias and USB waveform amplitude. The required resistance tolerance was 1%, and there were tight restrictions on the way it had to be routed on the PCB.

Regards, Allan

I guess I can live with some feature of a part being poorly documented (just not a rich, full life). But for support to be silent on this is the sort of thing I expect from companies with lesser reputations. I guess Analog's rep is in their parts, not their support. Has Analog's support gone overseas? Actually, as a customer, I don't mind outsourcing support if they do a good job of it. I've spoken and emailed with some good overseas support before. But mostly they are reading the results of knowledge base searches... the same as US based first line support.

I am curious about why you chose the Blackfin. I took a look at it a while back and came to the conclusion that it really doesn't offer much that other devices don't have and I got the impression that it is not used as much (meaning lower sales volumes) and so will not receive the same corporate level of attention in the way of new product development. I guess if it's a good fit for what ever you are currently working on use it, but what is the stand out feature for your current project? Or are you using it because you are already vested in it? Did I miscalculate and the Blackfin is actually a vibrant product line with new members on a regular basis?

Rick

Nice combination of simplicity, raw computing power, programmability in C++ and asm, peripheral set, reasonable cost and power consumption. BlackFin is good for the medium sized applications where you do all work in one processor and if you don't need the MMU.

Vladimir Vassilevsky DSP and Mixed Signal Design Consultant

USB high speed at 600MHz is a plus. Only 132K flash is a minus, especially for USB host. I would go for at least 256K.

Try their EngineerZone, e.g. this thread:

HTH, Bob