Lpc2000

Hi,

>You must be new to the low-cost micro controller scene because with
>most low-end micros (in my experience) the SS# pin is not normally
>driven by the master - it, or any other GPIO for that matter is driven
>by software to select a slave. This is not a Philips LPC thing - the
>AVR and many other micros act the same way.

I've been working with AVR for several years and I can tell you that the AVR
controllers does NOT need the pin to be forced high by hardware to act as a
master.

What you are describing is not possible for the LPC2106... the /SS pin
*must* be tied high on hardware for the processor to act as a master then
you will need another pin to act as a /SS pin where in an AVR and a lot of
other processors you can control the actual /SS pin in software like you
mentioned.


>However in my opinion, it is better to have software control over the
>SS# pin since it would otherwise preclude multiple slaves when only
>one SS# pin is provided (as is the case with low-end micros).

Yes but not the case on Philips LPC2106 ! 


>As for the ADC on the LPC, I don't have any experience with this
>peripheral. However it is not uncommon for the inputs to not be 5V
>tolerant (if that what your rant was about) in mixed signal devices,
>or at least in peripherals/pins that interface with mixed signal
>silicon.

Philip write that every GPIO pin is 5V tolerant if what I've been hearing is
correct then if you have some >3V digital TTL input on a pin that shares the
ADC your result on another ADC pin will be incorrect and if that's true well
then Philips should stop making their apprentice design their processors !

>What exactly is wrong with the boot-loader? I like the standard and
>easy to use API it provides to the Flash. I also like the ability to
>have a fresh part on a PCB programmable without the need for JTAG (as
>do my verification and production peers).

I didn't say that there was something wrong with the bootloader but I've
been hearing a lot of bootloader related problems lately especially security
related postings and I would just like to see this explained more thoroughly
in a document instead of browsing the message archives...

That's why I suggested that we should make a list that new comers could
refer to.

Best regards
Lasse


-----Original Message-----
From: R M [mailto:rodlist@...] 
Sent: 30. november 2004 18:43
To: lpc2000@yahoogroups.com
Subject: [lpc2000] Re: LPC Series - Good things gone bad...




If you wanted a hardware controlled SS# peripheral then look at a more
complex/expensive device like the Coldfire 5282 which has a multi
channel SPI peripheral that bangs the SS# pins for you.









 
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