TinyG Boot Loader

Huge thanks to Kevin Osborn who got the bootloader working

If you are on this page because you want to upgrade the firmware on your TinyG board follow these links

• Updating TinyG Firmware
• How Do I Know if I Have the Bootloader?

If you are on this page because you want to program or modify the boot loader itself follow these links

• Flashing the Boot Loader onto the Xmega Chip
• Compiling the Boot Loader for TinyG
• Setting up Xboot as an AVRStudio4 Project

If you have no idea why you are on this page follow this link

• http://vimeo.com/82393638

How Do I Know if I Have the Bootloader?

TinyG's shipped from March 10, 2013 have a boot loader that supports flashing the TinyG firmware using AVRdude (aka the AVR109 protocol). You can tell if you have the boot loader if the Spindle Direction LED flashes when you hit reset:

• On hardware reset (reset button) or software reset (Control-X) the spindle direction bit will flash 4x/sec for about 3 seconds indicating the board is in boot loader mode. After that it will start the application. If no application is present it will revert to the boot loader, so the light will just keep flashing.

You can also manually enter the bootloader from the application:

• Issuing a boot command: $boot=1 or {"boot":1} will enter the boot loader and cause it to remain in the boot loader for 60 seconds before reverting to the application.

If the LED doesn't flash you don't have the bootloader. See Flashing the Boot Loader onto the Xmega Chip if you want do do this yourself. You can also return your board to us and we'll do it. Contact us if you want us to put the bootloader onto your board.

Advanced Topics

Flashing the Boot Loader onto the Xmega Chip

Update 5/22/13: We have had reports that programming (flashing) the boot loader using AtmelStudio6.0 or Studio6.1 can report a verification error. The boot loader is actually loaded correctly and does work, in spite of this error (so far no counter examples have been reported). Flashing using AVRStudio4 does not report these errors.

The following instructions are how to flash the boot loader using Atmel Studio6. AVRStudio4 is similar, as would be command-line operation. These instructions use the xboot.hex file already in the project. You can get the xboot.hex file here. [xboot.hex] (https://raw.github.com/synthetos/TinyG/master/xboot/xboot/xboot.hex) NOTE: You need to right click and save as on the xboot.hex link to download the hex file correctly. The hex should be all you need to get the bootloader onto the chip, but if you want to compile the bootloader yourself go to the next section: Compiling the Boot Loader for TinyG

Step 1. Get the right programmer. The xmega requires PDI programming. Use the Atmel AVRISP mkii or some other programmer that supports PDI programming. Plug the programmer into TinyG and apply power to TinyG.

Step 2. Bring up Studio6.2 (or later) and the device programming panel. Look under Tools / Device Programming

• In the programming panel verify Tool is AVRISP mkii, the device is ATxmega192A3 and the interface is PDI. Hit Apply, then Read. You should see the Device signature and voltage field populate. Voltage should be 3.2v or thereabouts.

Step 3. Set the fuses. Go to Fuses and set according to here. Hit Program to program the fuses.

Step 4. Go to Memories. Select xboot.hex in the Flash section. Hit Program.

If this all worked you will see the Spindle Direction light will continue to flash. You now need to load the TinyG firmware onto your board. To to that follow the instructions [here].(https://github.com/synthetos/TinyG/wiki/TinyG-TG-Updater-App)

Compiling the Boot Loader for TinyG

Use these instructions if you want to change the xboot.hex file. If all you want to do is flash it onto TinyG see the previous section.

The boot loader is Alex Forencich's xboot which can be found in the xboot directory in the main TinyG git tree. This xboot has the settings and modifications for use on TinyG.

Getting Xboot to work from the native Makefile

Bring up a cmd window and navigate to the working directory. Run the command:

make conf/x192a3.conf.mk

Step 1. The command line you need is:
make conf\x192a3.conf.mk

You should see something like this:

Z:\Alden\Projects\proj38_TinyG\TinyG\xboot\xboot>make conf/x192a3.conf.mk
cp conf/x192a3.conf.mk config.mk
make
make[1]: Entering directory `Z:/Alden/Projects/proj38_TinyG/TinyG/xboot/xboot'

-------- begin --------
avr-gcc (AVR_8_bit_GNU_Toolchain_3.3.0_364) 4.5.1
Copyright (C) 2010 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


Size before:
xboot.elf  :
section       size       addr
.text       0x1066    0x30000
.bss         0x206   0x802000
.stab       0x5b68        0x0
.stabstr   0x17403        0x0
Total      0x1e1d7



Generating config.h for atxmega192a3

Compiling: xboot.c
avr-gcc -c -mmcu=atxmega192a3 -I. -gstabs   -Os -funsigned-char -funsigned-bitfi
elds -fpack-struct -fshort-enums -ffunction-sections -fdata-sections -fno-jump-t
ables -Wall -Wa,-adhlns=xboot.lst  -Wstrict-prototypes -std=gnu99 -MD -MP -MF .d
ep/xboot.o.d -DF_CPU=32000000L -DUSE_CONFIG_H xboot.c -o xboot.o

Compiling: uart.c
avr-gcc -c -mmcu=atxmega192a3 -I. -gstabs   -Os -funsigned-char -funsigned-bitfi
elds -fpack-struct -fshort-enums -ffunction-sections -fdata-sections -fno-jump-t
ables -Wall -Wa,-adhlns=uart.lst  -Wstrict-prototypes -std=gnu99 -MD -MP -MF .de
p/uart.o.d -DF_CPU=32000000L -DUSE_CONFIG_H uart.c -o uart.o

Compiling: api.c
avr-gcc -c -mmcu=atxmega192a3 -I. -gstabs   -Os -funsigned-char -funsigned-bitfi
elds -fpack-struct -fshort-enums -ffunction-sections -fdata-sections -fno-jump-t
ables -Wall -Wa,-adhlns=api.lst  -Wstrict-prototypes -std=gnu99 -MD -MP -MF .dep
/api.o.d -DF_CPU=32000000L -DUSE_CONFIG_H api.c -o api.o

Linking: xboot.elf
avr-gcc -mmcu=atxmega192a3 -I. -gstabs   -Os -funsigned-char -funsigned-bitfield
s -fpack-struct -fshort-enums -ffunction-sections -fdata-sections -fno-jump-tabl
es -Wall -Wa,-adhlns=config.lst  -Wstrict-prototypes -std=gnu99 -MD -MP -MF .dep
/xboot.elf.d -DF_CPU=32000000L -DUSE_CONFIG_H xboot.o flash.o eeprom_driver.o ua
rt.o i2c.o fifo.o watchdog.o api.o sp_driver.o --output xboot.elf -Wl,-Map=xboot
.map,--cref -Wl,--gc-sections    -lm -Wl,--section-start=.text=0x030000

Creating load file for Flash: xboot.hex
avr-objcopy -O ihex -R .eeprom xboot.elf xboot.hex

Creating load file for boot section: xboot-boot.hex
avr-objcopy -O ihex --change-addresses -0x030000 xboot.hex xboot-boot.hex

Creating load file for EEPROM: xboot.eep
avr-objcopy -j .eeprom --set-section-flags=.eeprom="alloc,load" \
        --change-section-lma .eeprom=0 -O ihex xboot.elf xboot.eep
c:\Program Files\Atmel\AVR Tools\AVR Toolchain\bin\avr-objcopy.exe: --change-sec
tion-lma .eeprom=0x00000000 never used

Creating Extended Listing: xboot.lss
avr-objdump -h -S xboot.elf > xboot.lss

Creating Symbol Table: xboot.sym
avr-nm -n xboot.elf > xboot.sym

Size after:
xboot.elf  :
section       size       addr
.text       0x1066    0x30000
.bss         0x206   0x802000
.stab       0x5b68        0x0
.stabstr   0x17403        0x0
Total      0x1e1d7

Errors: none
-------- end --------

make[1]: Leaving directory `Z:/Alden/Projects/proj38_TinyG/TinyG/xboot/xboot'

Z:\Alden\Projects\proj38_TinyG\TinyG\xboot\xboot>

But beware - it only works in windows. Use cmd and navigate to the (lower) xboot directory something like: Z:\Username\Projects\...\TinyG\xboot\xboot\make conf\x192a3.conf.mk

It enters an infinite loop in Linux and generates this error in OSX

macintosh-3:xboot your-user-dir$ make conf\x192a3.conf.mk
.dep/fifo.o.d:1: *** multiple target patterns.  Stop.
macintosh-3:xboot your-user-dir$

You should now be ready to flash xboot.hex onto the xmega192. Refer to the Flashing... section, above.

Setting up Xboot as an AVRStudio4 Project

Xboot has been set up as an AVRStudio4 project (Windows only). use the xboot.aps project file.

Note: We abandoned trying to get it running under Studio 6 as it simply doesn't work. Xboot seems to only compile under the AVRGCC 4.3.3 (WinAVR 20100110). Studio 6 runs the AVR_8_bit_GNU_Toolchain_3.4.0_663 (4.6.2). For some reason code generated by the the newer compiler doesn't function - it fails during EEPROM write. Evidently this is a known bug - but it's not our bug, so time to move on. These are not the droids we are looking for.

You can either use the native makefile or have AS4 auto generate a makefile. The auto-generated option allows you to use the AVR simulator to debug - otherwise there is no functional difference.

Be aware that in order to generate the config.h file you must change x192a3.conf.mk and make it with the native makefile. The AVRStudio4 project does not run the config.h target.

Native Makefile

To use the native makefile check Use External Makefile in Project / Configuration Options.

Running the external make from AS4 does not create the config.h file. Manually run make conf/x192a3.conf.mk from a windows command line. You will have to do this initially and each time you change x192a3.conf.mk.

You want to use the xboot.hex in the xboot working directory.

Auto-generated Makefile

To use the auto-generated makefile do the following:

1. Generate config.h by running make conf/x192a3.conf.mk from a windows command line (as above). You will have to do this initially and each time you change x192a3.conf.mk.
2. Setup the xboot project configuration in Project \ Configuration Options

in the General section:
uncheck `Use External Makefile`
frequency = 32000000   (32 Mhz)
optimization = -Os

add the following to Custom Options, [All files]:
-DUSE_CONFIG_H
-ffunction-sections
-fdata-sections

add the following to Custom Options, [Linker Options]:
-Wl,--section-start=.text=0x030000
-Wl,-Map=xboot.map,--cref
-Wl,--gc-sections

You will want to use the xboot.hex file found in the default directory