Jump from application to Bootloader LPC546xx

[samuelguido]

I'm using a LPC54628. In the target application we do not have the ability to strap pins at reset to enter the boot loader's USB DFU/MSD interfaces for programming.

How can this be done without strapping pins at reset?

Is there a way to jump to the ROM boot code from the application?

I can't seem to find any clear picture on this would be accomplished.

Thank you

Sam Guido

[samuelguido]

Gustavo,

Yes that helped very much thank you!

In the manual, table 80 shows the ISP type selection. USB1 is not listed here as connection for the ISP. I ran an experiment and tried all combinations of 0-255 in byte 1. Values 0,1,4,6 and 8 did function as specified..

All other combinations (2,3,5,7 and 9-255) would enumerate the MSD on USB0 or USB1 if they were connected independently. If both USB0 and USB1 were connected at the same time, then it would always enumerate as a MSD on USB0. I'm a bit confused/concerned the manual doesn't specify USB1 as a ISP connection.

Strapping the pins (P0.4, P0.5 & P0.6) supports the DFU class on either USB0 or USB1 and I can see this when I strap the pins at reset as shown in table 5.

Does the reinvoke ISP routine support the DFU class on USB0/USB1 or is there a different way to invoke the DFU class? 

Thank you!

Sam...

[gusarambula]

Hello Sam,

Table 80 of the latest revision of the LPC546xx User manual (link below, you may need to login to download this document) does lists USB1 as well. My apologies for the confusion.

https://www.nxp.com/webapp/Download?colCode=UM10912

I hope that this information helps!

Regards,
Gustavo

[gusarambula]

Hello Sam Guido,

You may use the IAP Command “Reinvoke ISP” to invoke the bootloader in ISP mode. You can find more details in section 5.6.8 of the LPX546xx User Manual (UM10912).

I hope that this information helps!

Regards,
Gustavo