03-16-2021 04:56 AM
What is the optimum frequency for AXI master-slave when the system clock frequency is 250 MHz and JTAG frequency is 15 MHz? Thanks..
I currently set it to a clock_out of 200 MHz which seems to be very slow when I do read write. I am using KCU040 board and using a micro USB cable that connects to Digilent USB JTAG module on the board.
03-16-2021 05:30 AM
The JTAG and the AXI are not directly related
The JTAG can run at say 1 MHz or 10 MHz, the AXi does not care.
JTAG is used for debug and configuration, not real time access.
It runs over a serial link, similar in many ways to SPI,
03-16-2021 05:33 AM
@drjohnsmith Thanks! I am using JTAG for read/ write through MATLAB. I have implemented this design here:
Instead of external memory, I am just writing to slave register.
So you are saying whatever I am getting is my bottleneck? I can read 10k samples in 20 sec with a 15 MHz JTAG connection.
03-16-2021 05:39 AM
thats not bad speed for a serial link,
I'm amazed your getting 15 MHz reliably
JTAG is normally a few MHz, they must have made that board for speed.
dump Matalb might speed things up somewhat
but thats a different story
03-16-2021 05:58 AM
Not sure if I am getting truly 15 MHz. But both Matlab and Vivado shows that my connection speed is 15MHz. All I know is I can perform 10k read operations (10k MATLAB readmemory function) in 20 sec. Thanks anyway!