bootloader problem

doguhanpala · Joined: 05 Oct 2016 Posts: 120

Hello everyone,

I am newbie about bootloaders. I have read a few posts here. As i understand after the boodloader you can upload hex via usb or serial pins.

When the pic start up the bootloader checks for a message for a time period(if there is new hex) if there is no message it goes to the main function of the hex. If there is a message, writes the new hex.

First of all, is there any mistake (or mistakes probably) on the summary?

Secondly, i want to use the usb bootlader. I upload the ccs example code(i dont share it because of forum rules) but after that there is no communication. After usb communication the computer does not play usb voice and i cant see the hardware on device manager.

I checked about usb communication with a basic getc and putc function. I can send and see the chars via putty.

Any ideas about what am i doing wrong?

temtronic · Posted: Tue Apr 09, 2019 5:43 am

What version of Windows ? What other programs are running ?
What program did you download into the PIC ?
If the PIC program doesn't talk to the PC often, Windows will 'close' the USB port.
One of the bad things about USB is that it is NOT an interrupt driven serial port which the original comports were. It's 'polled' so whatever is attached to the PC USB HAS to access the PC on a regular basis to keep the USB comport 'open' or 'active'.
Jay

doguhanpala · Joined: 05 Oct 2016 Posts: 120