Re: CM11A hangup: Any better products?

[nobody@xxxxxxxxxxxx (Dave Houston)]

If you look at the schematic of the current RR501 you'll find about the same
number of components, including the same tuned transformer that's used with
the discrete oscillator, in the circuit driven by 120kHz from the PIC. It
needs alignment, too.

Joerg <notthisjoergsch@xxxxxxxxxxxxxxxxxxxxx> wrote:

>Hello Dan,
>
>> | > My theory is that the implementors of the CM11a were familiar with the
>> | > free-running oscillator design used in the TW523 and decided to adapt
>> | > it.  It was a proven circuit used in other X10 products as well.
>> |
>> | That could very well be but it would be pretty sad. Engineers are
>> | supposed to embrace new concepts when something can be realized at less
>> | cost.
>>
>> Of course, they might have done the analysis and decided that this solution
>> _was_ the most cost effective.  Typically X10 does a pretty good job of
>> "value engineering" in spite of what its competitors sometimes claim.
>
>It could be. However, every aligment procedure in production is usually
>a significant cost contributor. Even in China.
>
>> | > Does the 16C58 have the capability to route a timer to an output pin?  When
>> | > I wrote the enhanced version of my replacement firmware for the RR501 I used
>> | > a timer, but I had to swap some pins around to I could send it out via the
>> | > PWM block of the 16F628 (not doing actual PWM, of course).
>> |
>> | Frankly, I don't know the PIC series much. But it would surprise me if
>> | it wasn't possible. Pin swaps may be needed. Timer-based outputs are
>> | pretty easy on most uC like the MSP430 series even though they often do
>> | not have a dedicated PWM block.
>>
>> As far as I can tell, there is no obvious way to route the 16C58's TMR0
>> (the only one it has) to an output pin.  I don't think this function is
>> typically available on 16x PICs.  I was able to do it only by using that
>> PWM block in basically a pass-through mode, and a PIC with a PWM block may
>> not have been available (or cost effective) when the CM11a was designed.
>
>IIUC it outputs to TMR0 reg which indeed isn't so cool. But look at
>Figure 6-6. Maybe there is a way to pipe it through the WDT path. Unless
>PSA turns off the WDT Time-Out mux or that signal cannot go anywhere.
>This doesn't seem to be a very versatile uC. Or as they say in the UK,
>it doesn't float my boat.
>
>If it can't do all that maybe there is a better uC for X-10 than this
>one, at similar cost. Quite frankly it is the first uC I come across
>that seems to be unable to do PWM. Even ye olde C51 could do that.
>
>Regards, Joerg
>
>http://www.analogconsultants.com