Content originally posted in LPCWare by sathyan on Wed Apr 23 03:27:23 MST 2014
Hello!
I have brought LPC1756 Chips and made a custom board for it.
I tried to program the chip using the LPC1768 sample codes.
I am able to get the output for basic GPIO, UART Programs. But, when i tried communicating with USB Mass Storage, I am getting a weird problem.
After flashing the code using CoFlash tool configured in VECTRESET, i am able to send and recieve data through the usb of LPC1756. but when i reset the chip, i am unable to communicate with the USB! the program halts at Write Done Back Head Interrupt! But still on every reset i am able to get the outputs from UART and other GPIO but not from the USB!
Then i tried configuring the CoFlash tool in VECTRESET and clicked on blank check, then i am able to send and recieve data through USB!
But i cannot do this every time for a standalone device.
Please help me why am i not able to communicate through USB when the configuration is in SYSRESETREQ/HWRESET?
Why am i getting output only once for every program/blank check while the configuration is in VECTRESET?
Why does the reset button works only for the UART/GPIO and not the USB?
It seems like the memory map is simillar to both LPC1756 and LPC1768 for the UART and USB. Where am i making mistake?
please help!
Regards,
Sathyan