Lpc2000

I am starting a project which was planning to use an LPC210x and an
FTDI chip for a USB port.

I have been wondering about wether it would be wise to go for the
LPC214x family. The 8K DMA interface is just what I need, in the FTDI
solution I would have simply done a little protocoll to read and write
to the RAM.

But of course new solutions always have thier "gotchas". In particular
I am unsure about implementing the interface on the PC (and MAC/nix)
side.  Surfing this and other groups I know this has been a concern,
but of course these posts are dated.

Can anybody give me a quick status.....is the 214x still bleeding edge
or does it offer off the shelf solutions?

Dear nonuckingfumber,

OT: would it be possible to change your name into your real name, my
e-mail mind keeps thinking this is spam ...

Note that the lpc2148 is the only device with the DMA buffer, other
menbers of the lpc214x group do not have this function.

The ftdi solution will cost you something of 10-12 pins to interface to
the lpc210x if you take an ftd245 or a similar parallel interface. Using
an ft232 like device with a serial interface may not give you any
(technical) advantage on top of a standard UART connection...

The gotchas on the lpc2148 are still there. Look at the recent USB posts
in this group, it looks like USB is not fully stable and defenitely not
working on GCC (at least not publicly availale that is).

The qestion if you should go for ftdi or lpc2148 is not that easy to
answer. If you want a standard mass storage or HID device I would go for
lpc2148, if you do handle every driver detail in a specific
(windows/linux) application I would currently still select the ftdi -
shorter time-to-market.

USB driver development in both Linux and Windows is not an easy thing -
although it's easier in Linux than in Windows (but what is not ...)

Regards,

      Rob

> I am starting a project which was planning to use an LPC210x and an
> FTDI chip for a USB port.
>
> I have been wondering about wether it would be wise to go for the
> LPC214x family. The 8K DMA interface is just what I need, in the FTDI
> solution I would have simply done a little protocoll to read and write
> to the RAM.
>
> But of course new solutions always have thier "gotchas". In particular
> I am unsure about implementing the interface on the PC (and MAC/nix)
> side.  Surfing this and other groups I know this has been a concern,
> but of course these posts are dated.
>
> Can anybody give me a quick status.....is the 214x still bleeding edge
> or does it offer off the shelf solutions?

--- In lpc2000@yahoogroups.com, "Rob Jansen" <rob@m...> wrote:
>
> Dear nonuckingfumber,
> 
> OT: would it be possible to change your name into your real name, my
> e-mail mind keeps thinking this is spam ...

I **hate** names with numbers in them, after an hour spent trying to 
get Yahoo to accept any reasonable name with no numbers I ended up
with this one out of desperation ;-) Perhaps I will have another go
sometime...

> 
> Note that the lpc2148 is the only device with the DMA buffer, other
> menbers of the lpc214x group do not have this function.
> 
> The ftdi solution will cost you something of 10-12 pins to interface to
> the lpc210x if you take an ftd245 or a similar parallel interface. Using
> an ft232 like device with a serial interface may not give you any
> (technical) advantage on top of a standard UART connection...
> 

The 'advantage' is the that that serial ports are rapidly disaspearing
on the latest generation of compact computers.


> The gotchas on the lpc2148 are still there. Look at the recent USB posts
> in this group, it looks like USB is not fully stable and defenitely not
> working on GCC (at least not publicly availale that is).
> 
> The qestion if you should go for ftdi or lpc2148 is not that easy to
> answer. If you want a standard mass storage or HID device I would go for
> lpc2148, if you do handle every driver detail in a specific
> (windows/linux) application I would currently still select the ftdi -
> shorter time-to-market.

Yep, I think the FTDI is looking a winner, it's another chip but we
all know how mysterious bugs and hiccups under a big OS can lead to
unknown delays and frustrations.

A collegue pointed out that RS232/USB adapters are available in bulk
for a few dollars each, so I might just put a good RS232 driver that
can do 230K and throw in an adapter free just in case the user has no
serial port.

BTW, this collegue also pointed out that RS232 can be used with line
driver adapters (RS422) and ether/serial adapters where remote
conection is desired (a possibility), something that cannot be done
with USB. 

Hmmm....RS232, a disguting 1960's interface for connecting modems to
mainframes that just refuses to day....it is still the most flexible
option :-)

Thanks for the info.

nonuckingfumber wrote:

>--- In lpc2000@yahoogroups.com, "Rob Jansen" <rob@m...> wrote:
>  
>
>>Dear nonuckingfumber,
>>
>>OT: would it be possible to change your name into your real name, my
>>e-mail mind keeps thinking this is spam ...
>>    
>>
>
>I **hate** names with numbers in them, after an hour spent trying to 
>get Yahoo to accept any reasonable name with no numbers I ended up
>with this one out of desperation ;-) Perhaps I will have another go
>sometime...
>
>  
>
>>Note that the lpc2148 is the only device with the DMA buffer, other
>>menbers of the lpc214x group do not have this function.
>>
>>The ftdi solution will cost you something of 10-12 pins to interface to
>>the lpc210x if you take an ftd245 or a similar parallel interface. Using
>>an ft232 like device with a serial interface may not give you any
>>(technical) advantage on top of a standard UART connection...
>>
>>    
>>
>
>The 'advantage' is the that that serial ports are rapidly disaspearing
>on the latest generation of compact computers.
>
>
>  
>
>>The gotchas on the lpc2148 are still there. Look at the recent USB posts
>>in this group, it looks like USB is not fully stable and defenitely not
>>working on GCC (at least not publicly availale that is).
>>
>>The qestion if you should go for ftdi or lpc2148 is not that easy to
>>answer. If you want a standard mass storage or HID device I would go for
>>lpc2148, if you do handle every driver detail in a specific
>>(windows/linux) application I would currently still select the ftdi -
>>shorter time-to-market.
>>    
>>
>
>Yep, I think the FTDI is looking a winner, it's another chip but we
>all know how mysterious bugs and hiccups under a big OS can lead to
>unknown delays and frustrations.
>
>A collegue pointed out that RS232/USB adapters are available in bulk
>for a few dollars each, so I might just put a good RS232 driver that
>can do 230K and throw in an adapter free just in case the user has no
>serial port.
>
>BTW, this collegue also pointed out that RS232 can be used with line
>driver adapters (RS422) and ether/serial adapters where remote
>conection is desired (a possibility), something that cannot be done
>with USB. 
>
>  
>
Considering that in one installation, the customer didn't bother to read 
the manual and hooked up a long distance RS485 circuit: 14miles @ 1200 
baud!  We were very surprised that our equipment was working at that 
distance.  Normally, we would limit at somewhere near 5..7 miles.

Try doing that with USB...

Regards,

TomW


-- 
Tom Walsh - WN3L - Embedded Systems Consultant
http://openhardware.net, http://cyberiansoftware.com
"Windows? No thanks, I have work to do..."
----------------------------------------------------

> > >
> Considering that in one installation, the customer didn't bother to
read 
> the manual and hooked up a long distance RS485 circuit: 14miles @ 1200 
> baud!  We were very surprised that our equipment was working at that 
> distance.  Normally, we would limit at somewhere near 5..7 miles.
> 

At 1200 baud the wavelength of the 7th harmonic is 36Km, so 14 miles
is by no means critical from a transmission line POV.

Of course STP with a good conducter section is required, and at least
one side should be insulated if you are not going to have earthing
problems, especially in thunderstorms!