PicUsbBootloader

An USB bootloader for PICs. The bootloader firmware is meant to be compatible with the bootloader that comes factory-loaded on the "PICDEM Full Speed USB" demo board. This allows to use it with the fsusb implementation from Rick Luddy ( http://www.internetking.org/fsusb/ ).

Implementation State

The commands READ_VERSION (0x00), READ_FLASH (0x01), WRITE_FLASH (0x02) ERASE_FLASH (0x03), READ_CONFIG (0x06) have been implemented.

READ_EEDATA (0x04), WRITE_EEDATA (0x05), WRITE_CONFIG (0x07), UPDATE_LED (0x32) and RESET (0xFF) are not implemented.

Usage

Flash your PIC with the bootloader.hex. To change the firmware in the PIC pull down RB7 while connecting the PIC to the USB port. This enters bootloader mode and the firmware can be changed with fsusb (see http://www.internetking.org/fsusb/ ). You will need to adapt fsusb to search for the right VID/PID (fsusb_vendorID, fsusb_productID in fsusb.c).

I wrote my own bootloader host program in java that replaces fsusb. To use that one, locate the jar file named bootloader-*-jar-with-dependencies.jar in the directory java/bootloader/target. Start it with "java -jar bootloader-*.jar --help" for available commands/options.

The bootloader occupies the first page of the PIC (0x0000 - 0x0800). The interrupt vectors are remapped to 0x0800, 0x0808 and 0x0818. See the example subdirectory for a linker script you can use with your application. It contains also vectors.asm with a declaration of the remapped interrupt vectors.

Building

To build: Run make in the top level directory like this:

$ make VID=<vid> PID=<pid>

Where is the vendor id and pid is the product id you want to use for your device in hexadecimal without a leading "0x". Example:

$ make VID=0000 PID=0000

This will run make in the subdirectories, which in turn runs gpasm to compile and link the assembler sources to a .hex file.

There is a CI build of the firmware at travis-ci: http://travis-ci.org/holgero/PicUsbBootloader

Directories

18f13k50 Bootloader for the PIC 18f13k50 (works only on 18f13k50, the 18f14k50 has a different block write size).

18f2550 Bootloader for the PIC 18f2550 (might work on other PICs of the 18fx[45]5x family, but I did not try that).

java An implementation of a java bootloader for the host part. Has currently the same limitations as fsusb (it cannot read/write EEPROM) and does not read id locations and devid from the device. It writes only program memory.

License

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.