Re: [Sdcc-user] TUSB3210 and TUSB2136 (8051 with USB) headers, library and demo programs

[Johann G. <Joh...@gm...>]

Hi!

Thanks for your valuable feedback. I'll put all three answers together
to one EMail and answer at once.

Am Mittwoch, den 31.12.2008, 17:43 +0100 schrieb Maarten Brock:
> I'm not sure what to do with the library. SDCC currently has almost 
> no library code for 8051 derivatives and I'm not sure if we want to 
> start to. Most library functionality can be found on the SDCC OKR, 
> on www.8052.com or on the website of the manufacturer. But I'm just 
> one vote so let's see what others have to say about it.

Am Mittwoch, den 31.12.2008, 13:34 -0500 schrieb Dave McGuire:
>    Just chiming in with an opinion here.  I'm very happy to hear  
> about Hansi's library, and am looking forward to using it.  I don't,  
> however, think it should be distributed with SDCC.  It is not a part  
> of the compiler or the standard C library, so it shouldn't be  
> distributed with it.

I have to admin that I didn't look very closely at the libraries
supplied with SDCC but only remembered that there were some I2C routines
for the Cypress EZ-USB.

But I'm happy to ship my libraries with SDCC OKR or www.8052.com. I'll
submit them as soon I've integrated your feedback.

Am Mittwoch, den 31.12.2008, 18:11 +0100 schrieb Borut Razem:
> I have also a concern about the license you chosen: in the embedded 
> world LGPL is equal to GPL: it doesn't allow to statically link the 
> (L)GPL library with the closed source code. If you want to enable 
> linking your library with the proprietary code I propose GPL+LE - GPL 
> plus Library (or Runtime) Exception. See 
> http://sdcc.sourceforge.net/wiki/index.php?page=Library+License+Selection.

Thanks for this suggestion. I'll modify the library to GPL+LE.

Am Mittwoch, den 31.12.2008, 17:43 +0100 schrieb Maarten Brock:
> The headers could be included and I'm glad you already used 
> compiler.h. But I do not like anything I see in uctypes.h. NULL, 
> bool and the int's are all already defined in stdlib.h, stdbool.h 
> and stdint.h. Please use those.

Using 'bool' as defined by stdbool.h as a bit makes problems when using
functions with a bool return type and making a pointer to such a
function.

typedef bool (*BoolReturnFunc_t)();

bool TestFunc() {
  return true
}

void test() {
  BoolReturnFunc_t FuncPtr;
  FuncPtr = &TestFunc;   // <-- error
}

gives the error
  error 35: '&' illegal operand , address of bit variable

Probably this is just a bug report. I've modified all such functions to
return an uint8_t. For all others I use bool and stdbool.h.

I've also removed uctypes.h and use stdint.h everywhere. Thanks for the
hint that all this is already prepared. :-)

> And when compiling with --std-c89 you cannot use // comments nor 
> 'xdata'. Please use /* */ and __xdata instead.

Is the possibility to compile with --std-c89 mandatory?

I tried to compile with --std-c89 and it gives the warning
  warning 187: ISO C90 does not support flexible array members
for an "open" array element of
  typedef struct {
    ...
    int Field[];
  } name;
How can I get rid of this warning?

Everything else in the library I've changed to be --std-c89 compliant.

> Personally, I am totally against function implementations in header 
> files unless 'inline'd. But inline again is C99 only.

I'm too against implementations in .h files. Where did you find those?

> Finally, are you sure the TUSB is completely 8052 compatible? 
> Otherwise I'd prefer not to include 8052.h and copy the relevant 
> portions only.

Yes, the datasheet says:

 * Integrated 8052 Microcontroller With:
  ­ - 256 × 8 RAM for Internal Data
  ­ - 8K × 8 RAM Code Space Available for Downloadable Firmware From
Host
     or I2C Port.
  ­ - 512 × 8 Shared RAM Used for Data Buffers and Endpoint Descriptor
     Blocks (EDB)
   - Four 8052 GPIO Ports, Ports 0,1, 2, and 3
   - Master I2C Controller for External Slave Device Access
   -­ Watchdog Timer

So it is a real 8052 and not an 8051.

Bye
  Hansi