On Tue, Feb 07, 2006 at 11:42:27AM +0800, Chen Xiao Fan wrote:
> 
> 
> > -----Original Message-----
> > From: piclist-bounces@mit.edu 
> > [mailto:piclist-bounces@mit.edu] On Behalf Of Byron A Jeff
> >
> > It's not really a foreign concept. The 68HC11 implemented a 
> > bootstrap mode. Here's an app note describing it:
> >
> >Fundamentally it was a blank chip with a bootloader installed.
> 
> If you do not want to talk about PIC, yes all the Freescale
> 68HC908 flash parts have a monitor ROM inside. Even the 8-pin  
> MC68HC908QT1/2/4 have the monitor ROM inside. By the way,
> 68HC05/68HC11/68HC16 are no longer promoted by Freescale. 
> Freescale promotes more the 68HC908/HCS08 and 68HC912/HCS12 family.

The point still stands that a factory loaded bootloader could in
fact have utility.

> I need to check out the Freescale USB part since I am not so familiar
> with the HC908 parts and I do not like its high active current
> consumption compared to PICs and AVRs.
> 
> However the design of PIC MCU will not allow Microchip to install
> a bootloader inside without occupying programming space.

That's a tradeoff.

> Moreover many customers will not need the bootloader.

Doesn't matter. Under the presumption that someone doesn't need a
bootloader, it'll be gone the first time the chip is erased.

Of course the point is moot as Mchips doesn't put bootloaders into
any of their line.

> And there are many bootloaders out there.

Chicken and egg. If one doesn't like the default bootloader they can
use it to load up a bootloader that they did like.

I'm thinking this thread is wrung out. I plan to work on my serial
port code dump and bootloader firmware. Then anyone interested in
using it will have it available. 

BAJ
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