Search found 1461 matches

by YahooArchive
Thu Feb 14, 2013 1:55 pm
Forum: Software issues
Topic: Can I use TXD3 for GPIO
Replies: 1
Views: 3962

Re: Can I use TXD3 for GPIO

R9 through R11 are not loaded (they would be on the circuit(back) side of the
board. And would allow a different UART to be connected to the USB serial port.
So you can use TXD1, TXD3, RXD1, RXD3.
by YahooArchive
Thu Feb 14, 2013 1:54 pm
Forum: Software issues
Topic: Can I use TXD3 for GPIO
Replies: 1
Views: 3962

Can I use TXD3 for GPIO

I have a Superpro Plus and I am running out of pins. I see in the schematic that TXD3/TDX1/TDX0 are all jumpered together, same goes for the RDX's. I know that TDX0/RDX0 are for the programming interface so I don't want to mess with them but I want to use the others for GPOI. Can I do this on this b...
by YahooArchive
Thu Feb 14, 2013 1:52 pm
Forum: Software issues
Topic: GET or POST from ARMweb
Replies: 8
Views: 8781

Re: GET or POST from ARMweb

For a long time people have asked for client side services on the ARMweb, and we thought it would be too involved. But it finally go through to us all most of you really needed was the ability to do a GET or POST to a server, and in most cases you would ignore the data the server sends back. (we do ...
by YahooArchive
Thu Feb 14, 2013 1:46 pm
Forum: Software issues
Topic: QEI Interrupt Trouble
Replies: 6
Views: 8744

Re: QEI Interrupt Trouble

Dan, I posted below your quadrature example with one that I made work. I had been getting the fault messages as well. On start up the line that defines what sub to call when an interrupt happens. For the Quadrature it is this line. QUAD_ISR = ADDRESSOF QUADISR + 1 And that will tell the compiler to ...
by YahooArchive
Thu Feb 14, 2013 1:42 pm
Forum: Software issues
Topic: QEI Interrupt Trouble
Replies: 6
Views: 8744

Re: QEI Interrupt Trouble

>I keep getting a "FaultISR 0xFFFFFFF1 SCB->CFSR=0x00020000" error when the event occurs. PRINT is not re-entrant so you really should not use it inside an interrupt other than maybe to check to see that the interrupt occurs once. Once you see that the interrupt actually happened, then remove it. A ...
by YahooArchive
Thu Feb 14, 2013 1:41 pm
Forum: Software issues
Topic: QEI Interrupt Trouble
Replies: 6
Views: 8744

Re: QEI Interrupt Trouble

A while back I posted and got good advice about how to use the QEI hardware. I am only using it to count encoder steps and it works well. BUT, I have added so much to my program that polling the encoder is no longer effective because my main loop is about 250mS. Now I want to have the encoder moveme...
by YahooArchive
Thu Feb 14, 2013 5:27 am
Forum: Other Hardware interfaces
Topic: measuring voltages greater than 3.3V
Replies: 6
Views: 11915

Re: measuring voltages greater than 3.3V

Thanks Dan,

I should have made that clear.

"KeepIt SimpleStupid" I have standard value 0.1% resistors from 1950's and used
special value 0.01%? from Vishay 25 years ago.

Cheers
Will
by YahooArchive
Thu Feb 14, 2013 5:26 am
Forum: Other Hardware interfaces
Topic: measuring voltages greater than 3.3V
Replies: 6
Views: 11915

Re: measuring voltages greater than 3.3V

I agree with Will, but want to clarify how the resistor divider works. You would connect the 12K 1% resistor to your voltage source, then connect the 3K 1% resistor to the return (ground) of your source. Connect the remaining ends of the two resitors together, and also connect that junction to the i...
by YahooArchive
Thu Feb 14, 2013 5:26 am
Forum: Other Hardware interfaces
Topic: measuring voltages greater than 3.3V
Replies: 6
Views: 11915

Re: measuring voltages greater than 3.3V

I did not know that "pick your own value" resistors are available: http://www.digikey.com/product-search/en/resistors/precision-trimmed-resistors/6\ 6806?k=resistors 1% resistors are very common. Resistors in IC's can be passivated first and then "trimmed" using a laser through the passivation. Stan...
by YahooArchive
Thu Feb 14, 2013 5:26 am
Forum: Other Hardware interfaces
Topic: measuring voltages greater than 3.3V
Replies: 6
Views: 11915

Re: measuring voltages greater than 3.3V

Hi Mark,

Basic Ohms Law is what you need.