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hi, how to correct the phase error in QVCO? between I+ and I- is ok, same with Q+ and Q-. but between I+ and Q+ is not 90°, same with I- and Q-, they are closer to 45°.
Well in the testbench it does give X for low CLK. I think the underlying problem is that although the code is syntactially correct and works in simulator, there is no such resource )or set of resources) which matches the behavior modeled in the code thus it can't be synthesized. I'm doing some...
Re: VHDL - Signal xx cannot be synthesized, bad synchronous
I have followed your suggestion and still get the error.
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity ALU4bit is
Port ( x : in STD_LOGIC_VECTOR (3 downto 0)...
Re: VHDL - Signal xx cannot be synthesized, bad synchronous
that part of the code i don't think is causing problems. its when i address the state where clk is low, i want all outputs as X. i put the ELSE and i get 'bad synchronous description'. i take else out and initialize all outputs as X...
4 bit addition alu vhdl
The signals are all initialized to 0 after BEGIN in process statement. that is not enough? should the ELSE statement be in the 'output assignment' section then? i am using xilinx ise 9.2i, installing quartus 7.2 right now also.
IF s(3) = '0' THEN -- only consider CCR...
vhdl loop nested if then else
I still get the problem when I remove the ELSE statement. If I change to process(CLK) the error is still there...
very strange. I moved the code under the ELSE to the top where the input/output initialization is and doesnt work, but when I comment out this code i...
bad synchronous description
I have written a 4-bit ALU with CCR in VHDL, but when I try to obtain the Synthesis Report in Xilinx ISE 9.2i I get this error:
line 39: Signal C cannot be synthesized, bad synchronous description.
Line 39 is: " PROCESS(s, CLK) IS"
library IEEE;
use...
in architecture such as integer-n fhss (i.e. bluetooth), Fref must be equal to channel spacing (i.e. 1MHz), right?
(how) does this requirement differ for fractional n Σ-Δ?
A simple circuit!
why are there output pins? is this the top level or there is this the schematic of a symbol? make sure all pmos source is tied to vdd (from basic library, symbol) and in top level you have the vdd-vdc-gnd circuit. if you are really struggling, tie all pmos to vdc=1.8. does the...
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