Re: [myhdl-list] TypeError: Unexpected type with toVerilog

[Christopher F. <chr...@gm...>]

On 5/25/2012 6:09 AM, Jan Decaluwe wrote:
> On 05/24/2012 10:53 PM, Christopher Felton wrote:
>> On 5/24/2012 3:23 PM, Thoma HAUC wrote:
>>>        @always_comb
>>>        def outputenable():
>>>            if ((state == StateEnum.HSYNC) or (state == StateEnum.SYNC)
>>
>> I believe this is the issue.  There was a recent thread on this.  It
>> looks like enums fail in an always_comb.  A simple test case was
>> submitted recently.
>
> No, it was something else. Can you point me to the
> post/author of the other problem(s). I lost track a little
> but I will look into it with priority.
>
> Also, I propose to start using the bug tracker again, for
> formal bug reporting (after discussing it here preferably).
> Note that you can attach files to bug reports. I have
> done this for the bug that was just reported.
>

There have been a couple possible bugs reported.  It was my intent to 
submit patches with tests that exposed the issues.  Ah, such dreaming, 
time to work on fun things :)

Here is a snip from the a previous thread, using the enum in a 
always_comb didn't appear to work.  I tested quickly there could be a 
mistake on my part.

> I think your issue with using the enum() is in combination with the
> always_comb decorator.  The enums don't seem to work in an always_comb?
>   I didn't realize this limitation existed.  The following is the simple
> example I used (one of your previous questions) to see if this was true
> or not.
>
>      from myhdl import *
>
>      def case_ex1(clk, key, led):
>          tKey = enum('UP', 'DOWN', 'LEFT', 'RIGHT')
>          @always(clk.posedge)
>          def hdl():
>              if   key==tKey.UP:    led.next = 0xDE
>              elif key==tKey.DOWN:  led.next = 0xCA
>              elif key==tKey.LEFT:  led.next = 0xFB
>              elif key==tKey.RIGHT: led.next = 0xAD
>              else:                 led.next = 0x00
>
>          return hdl
>
>      def case_ex2(key, led):
>          tKey = enum('UP', 'DOWN', 'LEFT', 'RIGHT')
>          @always_comb
>          def hdl():
>              if   key==tKey.UP:    led.next = 0xDE
>              elif key==tKey.DOWN:  led.next = 0xCA
>              elif key==tKey.LEFT:  led.next = 0xFB
>              elif key==tKey.RIGHT: led.next = 0xAD
>              else:                 led.next = 0x00
>
>          return hdl
>
> In the above, the second does not convert correctly and fails the
> freevar check in the _analyzeGens, determines the enum is an unsupported
> type.

Regards,
Chris