This thread has become something of a wish list and although I would
probably add my 3 wishes to the list I guess there is a question we
could all ask ourselves. What would make me actually consider anything
other than a 2000 for a particular project? The 2000 line has to be a
competitive line for Philips, it does not matter if it were a great chip
or a throwback (take your pic), as long as it was good business.
Anyway, I could answer that question very quickly, it would be Ethernet
and USB (along with DMA). These are two devices which if implemented
externally would complicate what could of been a clean solution. At
present I must either choose something like Atmel or OKI, or else an
external bus 2000 coupled to these peripherals. Personally, I'd like to
stick to the 2000 line and what better incentive would there be then if
Uncle Phil could cook up some hot chips served along with the Mayonnaise
(Dutch thing).
Something else that whilst it does not seem as important does severely
curtail the use of the 2000 as a more general-purpose micro. This has
been brought up before and it is the I/O speed. Yeah, despite all those
yummy peripherals we still need to bit-bang sometimes, the faster the
better. This would mean little if the 2000 did not have an efficient
manner in which to execute these operations either and this has been
covered also.
When it comes to regulators and brownout reset circuits it is always
advantageous to have these incorporated on the device. But failing that
why can't Philips come out with a nice little dual regulator perhaps in
combo with the reset circuit. The use of LM117s in SOT-22(many)3 packs
is seemingly out of step with the low-power and size of the 2000. Yes,
TI have some nice regs which I have used, yet Philips can and really
should provide what amounts to companion chips that form part of the
product family.
When it comes to more UARTs, ADCs, etc., well, where do you draw the
line? I know I could use more UARTs but there are ways around this like
chaining multiple devices together over the SPI or I2C bus. But Uncle
Phil mentioned I2S and that caught my attention. I'd like to do audio
work with an ARM and what better way than to have a simple connection to
what are typically DSP peripherals.
As for the rest, well;
* Boundary Scan
Don't need it
* Combo Flash and RAM
Maybe less rather than more because that would also mean cheaper and
so I could replace my little micros as well with an LPC2002??!!!
* EEPROM
Would be nice but I can do this with external I2C devices easily.
Maybe the internal Flash could have a couple of small independent pages
perhaps?
* SDRAM, LCD, 80MHz
This is not the market for the 2000 now although it may become that.
There are plenty of manufacturers out there doing this now with ARM.
* Low and micro-power
This is always hard to define properly as to what is acceptable.
Sometimes it is fine if the whole chip is halted and oscillators stopped
as long as it can be woken up with a GPIO input change. Other times we
want to keep some power hungry peripheral active (Uart, Ethernet) and
have the unused sections sleep. Others want 32KHz RTC operation. Having
an on-board RC oscillator is prepatory to any low-power (and watchdog)
considerations. Stability, at least in the short-term vs accuracy is
more important in this regard. The RC oscillator can be calibrated
against the cystal allowing the crystal oscillator to be shut-down so
that timing can be maintained for some peripherals. Good or bad, at
least an RC watchdog circuit can wake-up the rest of the chip.
my2cents
--
Peter Jakacki