Hello,
Does anyone know if it is possible to modify the philips bootloader
code for the LPC chips to allow the bootloader to work in a half
duplex RS485 mode?
I am building a board who's primary form of communication will be a
2Wire half duplex RS485 link. To upload new firware at the PC end I
can easily use an RS232 to RS485 converter that has automatic gating.
I.e. it will switch between transmit and receive modes automatically.
the problem is the ARM end.
What I want to do on the ARM is to have one of its port lines control
the transmit receive state of the RS485 chip. This would require a
fairly simple mod to the bootloader code, if I had the source.
Does anyone have any suggestions? or alternative bootloader ideas.
On another tack, does anyone have any ideas about bootloader code for
the LPC214x that can use the USB port. This would be a nice option to
use in our product, use a usb port for firmware upgrading. This sort
of functionality is built into the Atmel SAM7 ARM chips
Thanks
Martin Honeywill
Half Duplex Bootloader Firmware
Started by ●October 6, 2005
Reply by ●October 6, 20052005-10-06
Hi Martin
We have a PC program which checks the boot loader version in an
LPC210x and loads the newest version if it is found not be be the
newest know one (there are some problems with older versions but
many chips still have them) and then loads a user software.
I assume it would not be a big job to modify this to ensure that it
will also work on half duplex links - RTS line could also be used
for control.
It takes about 2..3 days of work to knock up such a program.
I did the work for a customer (for factory programming - it is also
more reliable than the Philips utility, which programs the vector
check sum at the beginning and so risks a non-starting code if
interrupted, because it programs the vector check sum block as the
very last task) and so can not just give it away. If you are
interested and there is a small demand for such a utility then I
could probably get a licence agreement which will allow me to 'sell'
[sorry for the dirty word] the utility for an appropriate fee.
Tell me what you think.
Cheers
Mark Butcher
www.mjbc.ch --- In lpc2000@lpc2..., "mhoneywill" <martin.honeywill@k...>
wrote:
> Hello,
>
> Does anyone know if it is possible to modify the philips bootloader
> code for the LPC chips to allow the bootloader to work in a half
> duplex RS485 mode?
>
> I am building a board who's primary form of communication will be a
> 2Wire half duplex RS485 link. To upload new firware at the PC end I
> can easily use an RS232 to RS485 converter that has automatic
gating.
> I.e. it will switch between transmit and receive modes
automatically.
> the problem is the ARM end.
>
> What I want to do on the ARM is to have one of its port lines
control
> the transmit receive state of the RS485 chip. This would require a
> fairly simple mod to the bootloader code, if I had the source.
> Does anyone have any suggestions? or alternative bootloader ideas.
>
> On another tack, does anyone have any ideas about bootloader code
for
> the LPC214x that can use the USB port. This would be a nice option
to
> use in our product, use a usb port for firmware upgrading. This
sort
> of functionality is built into the Atmel SAM7 ARM chips
>
> Thanks
>
> Martin Honeywill
We have a PC program which checks the boot loader version in an
LPC210x and loads the newest version if it is found not be be the
newest know one (there are some problems with older versions but
many chips still have them) and then loads a user software.
I assume it would not be a big job to modify this to ensure that it
will also work on half duplex links - RTS line could also be used
for control.
It takes about 2..3 days of work to knock up such a program.
I did the work for a customer (for factory programming - it is also
more reliable than the Philips utility, which programs the vector
check sum at the beginning and so risks a non-starting code if
interrupted, because it programs the vector check sum block as the
very last task) and so can not just give it away. If you are
interested and there is a small demand for such a utility then I
could probably get a licence agreement which will allow me to 'sell'
[sorry for the dirty word] the utility for an appropriate fee.
Tell me what you think.
Cheers
Mark Butcher
www.mjbc.ch --- In lpc2000@lpc2..., "mhoneywill" <martin.honeywill@k...>
wrote:
> Hello,
>
> Does anyone know if it is possible to modify the philips bootloader
> code for the LPC chips to allow the bootloader to work in a half
> duplex RS485 mode?
>
> I am building a board who's primary form of communication will be a
> 2Wire half duplex RS485 link. To upload new firware at the PC end I
> can easily use an RS232 to RS485 converter that has automatic
gating.
> I.e. it will switch between transmit and receive modes
automatically.
> the problem is the ARM end.
>
> What I want to do on the ARM is to have one of its port lines
control
> the transmit receive state of the RS485 chip. This would require a
> fairly simple mod to the bootloader code, if I had the source.
> Does anyone have any suggestions? or alternative bootloader ideas.
>
> On another tack, does anyone have any ideas about bootloader code
for
> the LPC214x that can use the USB port. This would be a nice option
to
> use in our product, use a usb port for firmware upgrading. This
sort
> of functionality is built into the Atmel SAM7 ARM chips
>
> Thanks
>
> Martin Honeywill
