09-07-2017 03:33 PM
Dear all,
It is possible to use the NI 9411 for synchronous Serial Data reception?
For example, let have a stream at 10kbps data rate (33.3us/bit clock), from a serial sensor continuously feeding bits of data, separated by some given "delimiter".
Which would be the maximum data rate, if this module can handle 500ns?
Thanks in advance
Solved! Go to Solution.
09-07-2017 10:21 PM
Some additional notes:
Thanks in advance.
09-08-2017 01:05 AM - edited 09-08-2017 01:06 AM
Hi hypfco,
Which is the maximum speed of this module?. In the datasheet the figure "Update Rate" reads 0.5us.
Yes.
This means a clock of 2MHz can be configured for sampling digital inputs at this speed?
Yes.
Can this module lock at a given external (or internal?) clock for synchronous communication as receiver?.
No.
Why don't you use a serial port?
09-08-2017 06:22 AM
Is your data stream following a standard? It would be easier if you got a module that just used that standard. Otherwise, it seems like you should be able to do what you want if you are using a cRIO and program the FPGA.
09-08-2017 09:19 AM - edited 09-08-2017 09:23 AM
@GerdW:
Thanks for your answer.
Why don't you use a serial port?
Because the NI 9411 module brings 32 DI at $251 through 1 slot, with a 4 slot NI cRIO, while the NI 9871 module brings 4 DI ports at $716 through between 4-6 ports considering at least 2 devices per trunk, with a 8 slot NI cRIO.
09-08-2017 09:23 AM
09-08-2017 09:39 AM
@crossrulz wrote:
Is your data stream following a standard? It would be easier if you got a module that just used that standard. Otherwise, it seems like you should be able to do what you want if you are using a cRIO and program the FPGA.
True. I am thinking in saving resources by using a NI 9411 32ch 1slot , instead of a NI 9871 4ports 4-6slots. If some programming is required to make that reduction, i would accept it gladly.
No, the data will be fed through a small PCB card I will design for this purpose. For converting a SPI/I2C sensor into serial data.
09-08-2017 09:40 AM
I made a mistake, i will restart the question.
09-08-2017 09:00 PM
hypfco wrote:
No, the data will be fed through a small PCB card I will design for this purpose. For converting a SPI/I2C sensor into serial data.
There are libraries out there for performing I2C and SPI with LabVIEW FPGA. You might want to look at those and skip your conversion board. Another option is a USB-8451 or USB-8452, which are USB devices specifically made for I2C and SPI. The LabVIEW API is really simple too.
09-09-2017 06:01 PM
@crossruiz,
Thanks for your answer.
Because i would use the data transmission between a large distance (more than 100m), i think the PCB interface will be required in any case.
Those I2C/SPI LabVIEW FPGA libraries will be really useful indeed.
Still, i am looking mainly for slot economy by choosing a module similar to the NI 9411 (and more similar to the NI 9403 as per my mistake). That's why i would prefer several channels modules + software configuration instead of few ports modules + ready to go configuration.