Hi,
I have recently purchased a TE0712-100T for my custom carrier board and uploaded the "Test board" Vivado 2017.2 project.
In addition, I have added an RTL module into the design which takes in a clock input and turns on an LED when bit 25 on a counter is 1. The VHDL code is pasted below.
From testing, I am able to turn on the LED by attaching to a constant high block in Vivado. However, my LED is not blinking with a clock from the MIG clock output while using my own RTL module. Further debugging shows that there is no output from any of the clock outputs on the SI5338.
I was wondering if Trenz Electronics have their own default configuration on the NVM of the SI5338, or is it up to the user to develop their own
bare-metal code to set up the "default configuration" shown in the clocking section of the TE0712 TRM?
Regards
Andrew
Quote
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use ieee.numeric_std.all;
entity led_test is
Port ( clk : in STD_LOGIC;
led : out STD_LOGIC);
end led_test;
architecture Behavioral of led_test is
constant max_count : natural := 48000000;
signal count : unsigned(32 downto 0) := (others => '0');
signal rst : std_logic;
begin
rst <= '0';
compteur : process(clk,rst)
begin
if rst = '1' then
count <= (others=>'0');
elsif rising_edge(clk) then
count <= count + 1;
end if;
end process compteur;
led <= STD_LOGIC(count(25));
end Behavioral;
Hi,
Si5338 has on TE0712 has default configuration:
- https://wiki.trenz-electronic.de/display/PD/TE0712+TRM#TE0712TRM-Clocking
It's possible to reconfigure SI5338 over I2C. We have no example online. But it's planned.
br
John
Hi John
Thank you for the reply. Does this mean that the Si5338 loads the default configuration during powering of the TE0712 module?
Regards
Andrew
Hi,
yes. You can check for example MGT RefCLK with our example design.
Description
- https://wiki.trenz-electronic.de/display/PD/TE0712+Test+Board#TE0712TestBoard-MGTReferenceCLKCounter:
Download
- https://shop.trenz-electronic.de/en/Download/?path=Trenz_Electronic/TE0712/Reference_Design/2017.2/test_board
br
John
Hi John
again, thank you for the quick reply. The reference design looks promising. I have one more question, what Is the default input for the s5338? Would it be the onboard 25Mhz clock or input 1 and 2? I potentially want to use a PCIe 100Mhz clock as the input instead of the onboard crystal so the PCIe FPGA firmware would be in sync.
Regards
Andrew
Hi,
SI5338 use 25MHz, but can also select external source:
- https://wiki.trenz-electronic.de/display/PD/TE0712+TRM#TE0712TRM-Clocking
But there is also a second MGT REFCLK available on B2B:
- https://wiki.trenz-electronic.de/display/PD/TE0712+TRM#TE0712TRM-BlockDiagram
- https://shop.trenz-electronic.de/en/Download/?path=Trenz_Electronic/TE0712/REV02/Documents
br
John