How to write an "alias" statement

Hi,

I have a register array with each register having (pointer & data), now I hope to display each of two parts using 2 different names for easy reading in simulation.

Here is code defining the register array R:
type R_Type is array(0 to R_SIZE) of unsigned(POINTER_BITS + DATA_BITS-1 downto 0); 
signal	R : R_Type;
 alias P1 : it shows R array part of (DATA_BITS-1 downto 0);
 alias P2 : it shows R array part of (POINTER_BITS-1 downto DATA_BITS);

How to write the 2 alias statements in VHDL 2002 or 2008?

Thank you.

Weng

On Tuesday, December 4, 2018 at 12:37:54 PM UTC-8, Weng Tianxiang wrote:
> Hi,
> 
> I have a register array with each register having (pointer & data), now I hope to display each of two parts using 2 different names for easy reading in simulation.
> 
> Here is code defining the register array R:
> type R_Type is array(0 to R_SIZE) of unsigned(POINTER_BITS + DATA_BITS-1 downto 0); 
> signal	R : R_Type;
>  alias P1 : it shows R array part of (DATA_BITS-1 downto 0);
>  alias P2 : it shows R array part of (POINTER_BITS-1 downto DATA_BITS);
> 
> How to write the 2 alias statements in VHDL 2002 or 2008?
> 
> Thank you.
> 
> Weng

Here is my version for the answer:
type P1_Type array(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0);

 alias P1 : P1_Type := R(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0);

It should work on both 2002/2008 VHDL.

Thank you.

Weng

On Tuesday, December 4, 2018 at 10:39:48 PM UTC-5, Weng Tianxiang wrote:
> On Tuesday, December 4, 2018 at 12:37:54 PM UTC-8, Weng Tianxiang wrote:
> > Hi,
> > 
> > I have a register array with each register having (pointer & data), now I hope to display each of two parts using 2 different names for easy reading in simulation.
> > 
> > Here is code defining the register array R:
> > type R_Type is array(0 to R_SIZE) of unsigned(POINTER_BITS + DATA_BITS-1 downto 0); 
> > signal	R : R_Type;
> >  alias P1 : it shows R array part of (DATA_BITS-1 downto 0);
> >  alias P2 : it shows R array part of (POINTER_BITS-1 downto DATA_BITS);
> > 
> > How to write the 2 alias statements in VHDL 2002 or 2008?
> > 
> > Thank you.
> > 
> > Weng
> 
> Here is my version for the answer:
> type P1_Type array(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0);
> 
>  alias P1 : P1_Type := R(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0);
> 
> It should work on both 2002/2008 VHDL.

"Should" work???  Haven't you tested it? 

  Rick C. 

  Tesla referral code - https://ts.la/richard11209

On Wednesday, December 5, 2018 at 5:37:26 AM UTC-8, gnuarm.del...@gmail.com wrote:
> On Tuesday, December 4, 2018 at 10:39:48 PM UTC-5, Weng Tianxiang wrote:
> > On Tuesday, December 4, 2018 at 12:37:54 PM UTC-8, Weng Tianxiang wrote:
> > > Hi,
> > > 
> > > I have a register array with each register having (pointer & data), now I hope to display each of two parts using 2 different names for easy reading in simulation.
> > > 
> > > Here is code defining the register array R:
> > > type R_Type is array(0 to R_SIZE) of unsigned(POINTER_BITS + DATA_BITS-1 downto 0); 
> > > signal	R : R_Type;
> > >  alias P1 : it shows R array part of (DATA_BITS-1 downto 0);
> > >  alias P2 : it shows R array part of (POINTER_BITS-1 downto DATA_BITS);
> > > 
> > > How to write the 2 alias statements in VHDL 2002 or 2008?
> > > 
> > > Thank you.
> > > 
> > > Weng
> > 
> > Here is my version for the answer:
> > type P1_Type array(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0);
> > 
> >  alias P1 : P1_Type := R(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0);
> > 
> > It should work on both 2002/2008 VHDL.
> 
> "Should" work???  Haven't you tested it? 
> 
>   Rick C. 
> 
>   Tesla referral code - https://ts.la/richard11209

Hi Rick,

You have been the most famous contributor in FPGA and VHDL group for more than 10 years. If you answer, there is a problem.

Here is a correction version:

type P1_Type array(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0); 

 alias P1 : P1_Type := R(0 to R_SIZE)(DATA_BITS-1 downto 0); 

Currently I have no Modelsim working and have no means to test. If you are kind enough, please test it. I think it SHOULD work.

Thank you.

Weng

On Wednesday, December 5, 2018 at 11:07:50 AM UTC-5, Weng Tianxiang wrote:
> On Wednesday, December 5, 2018 at 5:37:26 AM UTC-8, gnuarm.del...@gmail.com wrote:
> > On Tuesday, December 4, 2018 at 10:39:48 PM UTC-5, Weng Tianxiang wrote:
> > > On Tuesday, December 4, 2018 at 12:37:54 PM UTC-8, Weng Tianxiang wrote:
> > > > Hi,
> > > > 
> > > > I have a register array with each register having (pointer & data), now I hope to display each of two parts using 2 different names for easy reading in simulation.
> > > > 
> > > > Here is code defining the register array R:
> > > > type R_Type is array(0 to R_SIZE) of unsigned(POINTER_BITS + DATA_BITS-1 downto 0); 
> > > > signal	R : R_Type;
> > > >  alias P1 : it shows R array part of (DATA_BITS-1 downto 0);
> > > >  alias P2 : it shows R array part of (POINTER_BITS-1 downto DATA_BITS);
> > > > 
> > > > How to write the 2 alias statements in VHDL 2002 or 2008?
> > > > 
> > > > Thank you.
> > > > 
> > > > Weng
> > > 
> > > Here is my version for the answer:
> > > type P1_Type array(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0);
> > > 
> > >  alias P1 : P1_Type := R(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0);
> > > 
> > > It should work on both 2002/2008 VHDL.
> > 
> > "Should" work???  Haven't you tested it? 
> > 
> >   Rick C. 
> > 
> >   Tesla referral code - https://ts.la/richard11209
> 
> Hi Rick,
> 
> You have been the most famous contributor in FPGA and VHDL group for more than 10 years. If you answer, there is a problem.

First, don't assume that a "frequent" contributor means someone who knows anything.  Then notice I only asked a question.  I didn't say there was anything wrong.  


> Here is a correction version:
> 
> type P1_Type array(0 to R_SIZE) of unsigned(DATA_BITS-1 downto 0); 
> 
>  alias P1 : P1_Type := R(0 to R_SIZE)(DATA_BITS-1 downto 0); 
> 
> Currently I have no Modelsim working and have no means to test. If you are kind enough, please test it. I think it SHOULD work.

You can download a copy of nearly any FPGA vendor's tools and use whichever simulator they include.  I would run it for you, but I am pretty busy at the moment.  I'm with a friend who has gone through surgery and I have business tasks to deal with.  Sorry I can't help more. 

  Rick C. 

  Tesla referral code + https://ts.la/richard11209