how to write code to get a nice RTL schematics

[iggyboy]

how to write rtl

Hello. Noob warning.

I wrote my first thingy in vhdl and now I don't know how to rewrite the code to get an acceptable RTL schematics. What I get now just doesn't look like a schematics, it's more like a bunch of connected stuff that looks ugly.

For example: there are several prescalers in my design, counters etc, yet there is nothing like that in the RTL. I google around and there are RTL schematics that just speak to you, but I can't get an example to immitate the coding style to produce similar results.

I already started breaking the design into components and such but the RTL stays the same.


What do you suggest? How do I improve my coding style?

:|

 

[wpchan05]

how to write good rtl

a good rtl is a result of good schematic. You won't know what happen if you dont know the schematic. this is my opinion.

 

[iggyboy]

rtl schematics

Hello and thanks for the reply, which unfortunatelly I did not understand. Beeing a noob and all. But you are wellcome to elaborate, wpchan05.

However I just solved my problem by rewriting most of my code with componets so all the active code that remained were signals which connected those components and the I/O connections. I speculate that by doing so you can taylor the aperance of the RTL schematics in great detail.

But if anyone has any further advice, you are always welcome to share your wisdom.

 

[wpchan05]

how to write schematics

Hello and thanks for the reply, which unfortunatelly I did not understand. Beeing a noob and all. But you are wellcome to elaborate, wpchan05.

Always design your hardware beofre coding in rtl.

 

[lucbra]

how to write a register transfer language code

1. Think logic, not software
Have in mind that the final code will fit in an ASIC or FPGA or CPLD, and not been run on a microprocessor or microcontroller!

2. Top->Down or Bottom->Up: don't mix
I tend to code bottom up as it divides difficult tasks in many easy tasks. Try (simulate and synthesis) these small blocks first. If these are satisfactory, then you'll keep a nice design.

3. code with components
you figured this one out allready

good luck

 

[barry]

My two cents: Yes, you should code while thinking about components, but if your goal is a pretty schematic: good code doesn't necessarily mean a nice schematic. I think if you have a perfectly good state machine with more than a few states, you're going to get an ugly schematic.

 

[oursriharsha]

i suggest you read the Pong P chu book on RTL coding .
it gives you a good insight of the design as well as the coding.