On Sun, 21 May 2006 08:57:53 -0700, you wrote:

>Mike Harrison wrote:
>> On Sun, 21 May 2006 02:47:36 -0700, you wrote:
>>
>>   
>>> Denny Esterline wrote:
>>>     
>>>>> They work GREAT, Denny. smaller chip than before, and NO
>>>>> clock is needed; in fact it can SUPPLY 6M/12M/24M your choice.
>>>>> The clock is sync'd to the USB Port clock, so is very precise.
>>>>>     
>>>>>         
>>>> Glad to here it, but this one isn't *just* the chip. They've embedded the chip in the USB "A" plug and added 6 feet of cable terminated to a female 0.1" header connection. 
>>>>
>>>> With four I/O pins with the ability to do bit bang, is anybody else thinking "trivial low voltage PIC programmer"?
>>>>   
>>>>       
>>> I looked at that, too, but I think it is too slow to be practical as a 
>>> programmer.
>>>     
>>
>> But would still be potentially useful, e.g. to provide a firmware progging mechanism for products
>> that use a lower-end PIC wich doesn't have  self-programming capability.
>>
>> My only criticism of the chip is that they didn't provide a 4MHz clock-out option, A lot of PIC apps
>> out there use 4MHz and this would have made upgrading slightly easier, and would have been trivial
>> to implement,
>>
>>   
>No, but a SOT23 flipflop could divide the 6Mhz by 2, could you use 3Mhz? 
>or use a dual FF wired as divide by 3 and use the 12Mhz
>to get 4 Mhz?
>

That kinda defeats the point of the minimum component count though... in practice I just modify the
code to run at 6MHz. My point was simply that 4MHz would have been a very useful addition to the
selection for minimal extra silicon. 


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