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Microchip PICs don't come pre-installed with a bootloader firmware??

Started by Unknown December 22, 2005
I am just learning about Microchips's bootloader capabilites. What is
not clear from any of the documentation I've read is whether the chips
with bootloading capabilities ship with the bootloader firmware
installed. Some posts in this group indicate that you have to add the
firmware yourself with an ICSP, which of course requires a hardware
programmer and the corresponding software.

This may sound like a dumb question, but if that is true, why?? Why
wouldn't Microchip just burn the chips with the bootloader so that all
of us poor developers only need to connect the chip to a serial port
and do an instant download of our application code without requiring a
hardware programmer. Am I missing something here?

One additional note. I read in Microchip's AN581 doc that they supply a
program called Quick Programmer used to program / communicate with a
bootloader. I couldn't find such a product on their web site. Has this
been integrated into their MPLAB?

Thanks for your response
Johann Blake

<johannblake@yahoo.com> wrote in message
news:1135238471.275611.20580@g49g2000cwa.googlegroups.com...
> I am just learning about Microchips's bootloader capabilites. What is > not clear from any of the documentation I've read is whether the chips > with bootloading capabilities ship with the bootloader firmware > installed. Some posts in this group indicate that you have to add the > firmware yourself with an ICSP, which of course requires a hardware > programmer and the corresponding software. > > This may sound like a dumb question, but if that is true, why?? Why > wouldn't Microchip just burn the chips with the bootloader so that all > of us poor developers only need to connect the chip to a serial port > and do an instant download of our application code without requiring a > hardware programmer. Am I missing something here?
The point you miss is that some don't want a bootloader because it eats memory. Also when Microchip installs a bootloader, does it meet your requirements? Maybe you want a simple bootloader to load your programs, but I would want a more secure bootloader with encryption so that people who get my images to load, cannot disassemble those images and "steal" my design. So in short: the requirements for a bootloader can be very different for anyone and it would be therefore pointless to preload a bootloader. Meindert
It's fair to say that most of the PIC business is either factory programmed or 
in-circuit programmed in high quantities. There is no reason to instal a bootloader 
for either of these situations. These guys sell a billion PICs a year, folks...


I know of companies who program their own bootloaders into PICs but they are for 
specific communications or security requirements.

-Andrew M



"Meindert Sprang" <mhsprang@NOcustomSPAMware.nl> wrote in message 
news:11qkrbm85844g7e@corp.supernews.com...
> <johannblake@yahoo.com> wrote in message > news:1135238471.275611.20580@g49g2000cwa.googlegroups.com... >> I am just learning about Microchips's bootloader capabilites. What is >> not clear from any of the documentation I've read is whether the chips >> with bootloading capabilities ship with the bootloader firmware >> installed. Some posts in this group indicate that you have to add the >> firmware yourself with an ICSP, which of course requires a hardware >> programmer and the corresponding software. >> >> This may sound like a dumb question, but if that is true, why?? Why >> wouldn't Microchip just burn the chips with the bootloader so that all >> of us poor developers only need to connect the chip to a serial port >> and do an instant download of our application code without requiring a >> hardware programmer. Am I missing something here? > > The point you miss is that some don't want a bootloader because it eats > memory. Also when Microchip installs a bootloader, does it meet your > requirements? Maybe you want a simple bootloader to load your programs, but > I would want a more secure bootloader with encryption so that people who get > my images to load, cannot disassemble those images and "steal" my design. So > in short: the requirements for a bootloader can be very different for anyone > and it would be therefore pointless to preload a bootloader. > > Meindert > >
Thanks for insight. I wasn't aware that the bootloader was using the
same memory space that my app would use. Too bad that Microchip doesn't
just include a built-in bootloader separate from the memory space used
for applications. This could just be a basic bootloader to
download/upload code or data. They could even allow you to set a
password to avoid the problem that you mentioned.

As I now see it, the point of the bootloader really is meant for after
production purposes. It doesn't appear to be possible to avoid using a
hardware programmer at this stage.

Thanks again
Johann

On 22 Dec 2005 00:01:11 -0800, johannblake@yahoo.com wrote:

>I am just learning about Microchips's bootloader capabilites. What is >not clear from any of the documentation I've read is whether the chips >with bootloading capabilities ship with the bootloader firmware >installed. Some posts in this group indicate that you have to add the >firmware yourself with an ICSP, which of course requires a hardware >programmer and the corresponding software. > >This may sound like a dumb question, but if that is true, why?? Why >wouldn't Microchip just burn the chips with the bootloader so that all >of us poor developers only need to connect the chip to a serial port >and do an instant download of our application code without requiring a >hardware programmer. Am I missing something here?
They can't program it in the factory because everybody's application is different. Different IO setup requirements, different comms interfaces, speeds & protocols. It would be a waste to spend money putting code in the chip that is only usefult to a small proportion of users.
johannblake@yahoo.com wrote:
> Thanks for insight. I wasn't aware that the bootloader was using the > same memory space that my app would use. Too bad that Microchip doesn't > just include a built-in bootloader separate from the memory space used > for applications. This could just be a basic bootloader to > download/upload code or data. They could even allow you to set a > password to avoid the problem that you mentioned.
I consider the JTAG download support a bootstrap loader. A lot of companies provide simple programmers based on this. The MSP430 has both a JTAG programming interface and a asynchronous serial bootloader. The async version resides in user space. I have used it because it requires few pins, but I believe it is a little slower. -- Thad
Meindert Sprang wrote:

> The point you miss is that some don't want a bootloader because it eats > memory. Also when Microchip installs a bootloader, does it meet your > requirements? Maybe you want a simple bootloader to load your programs, > but I would want a more secure bootloader with encryption so that people > who get my images to load, cannot disassemble those images and "steal" my > design. So in short: the requirements for a bootloader can be very > different for anyone and it would be therefore pointless to preload a > bootloader. >
better to use a decent micro like the 8052 variants from Philips. All come with a built in bootloader in ROM that does not eat into your program space. IAn
"Ian Bell" <ruffrecords@yahoo.com> wrote in message
news:doep4t$7mq$1@slavica.ukpost.com...
> better to use a decent micro like the 8052 variants from Philips. All come > with a built in bootloader in ROM that does not eat into your program > space.
All? The 87C52 I use doesn't have one.... Meindert
In article <doep4t$7mq$1@slavica.ukpost.com>, Ian Bell
<ruffrecords@yahoo.com> writes
>Meindert Sprang wrote: > >> The point you miss is that some don't want a bootloader because it eats >> memory. Also when Microchip installs a bootloader, does it meet your >> requirements? Maybe you want a simple bootloader to load your programs, >> but I would want a more secure bootloader with encryption so that people >> who get my images to load, cannot disassemble those images and "steal" my >> design. So in short: the requirements for a bootloader can be very >> different for anyone and it would be therefore pointless to preload a >> bootloader. > >better to use a decent micro like the 8052 variants from Philips. All come >with a built in bootloader in ROM that does not eat into your program >space.
I wish more microcontrollers would offer built-in ROM bootloaders. How many products have you ever used or owned that offered flash updating to the end user (motherboards, modems, satellite/freeview tv decoders, etc.) that said somewhere in the flash upgrade procedure instructions something to the effect of "interrupting this process may permanently damage the product". I interpret this to mean "we cost-cut the product so much that there is no ROM bootloader and if you get a power-cut, any form of serious glitch, crash, or any other type of failure, you might end up with a dead product that needs to be returned to the factory", which is often too expensive a repair option. It may only be a small risk, but I don't want to tell my customer 9000 miles away that the hex file I just sent him will work but that there is a small chance he'll have to send the equipment here instead. Protecting a bootloader in a flash boot block would help, but still isn't guaranteed. Adding an EPROM for this purpose alone is too expensive. By contrast, the last two major product developments I have done used microcontrollers with primitive ROM bootloaders. These allow me to absolutely guarantee a means by which the end user can recover from a faulty flash upgrade attempt regardless of what state the contents of flash are. If I require security or other features I can use the primitive bootloader to download a complex bootloader and continue from there to download the full firmware image. I may only end up using the primitive bootloader as a fail-safe if the regular upgrade process fails, but at least the option is there, and effectively "hard-wired" into the chip. The ROM only needs to be typically a few hundred bytes for a primitive bootloader and typically an I/O pin to activate it on bootup.
johannblake@yahoo.com wrote:
> I am just learning about Microchips's bootloader capabilites. What is > not clear from any of the documentation I've read is whether the chips > with bootloading capabilities ship with the bootloader firmware > installed. Some posts in this group indicate that you have to add the > firmware yourself with an ICSP, which of course requires a hardware > programmer and the corresponding software. > > This may sound like a dumb question, but if that is true, why?? Why > wouldn't Microchip just burn the chips with the bootloader so that all > of us poor developers only need to connect the chip to a serial port > and do an instant download of our application code without requiring a > hardware programmer. Am I missing something here? > > One additional note. I read in Microchip's AN581 doc that they supply a > program called Quick Programmer used to program / communicate with a > bootloader. I couldn't find such a product on their web site. Has this > been integrated into their MPLAB?
There are several ways to communicate with a processor. Just that it has a UART doesn't mean this is the to be used communication channel. SPI, external UART, Ethernet come to my mind. Then when you already communicate with a processor, then you'd wish the bootloader to have the same protocol such that it fits into your application. Rene -- Ing.Buero R.Tschaggelar - http://www.ibrtses.com & commercial newsgroups - http://www.talkto.net