Μ
µ == Micro
ATtiny85[edit]
Boot Loader[edit]
micronucleus is a 2Kb boot loader that provides a bit banged USB interface for directly updating user code without teh need for a programming device or dedicated USB to UART/Serial hardware.
https://github.com/micronucleus/micronucleus
A new ATtiny85 chip will need a time operation, i.e., be flashed with this bootloader. avrdude is a useful solution for this, and the following demonstrates such process with a Bus Pirate.
Check proper connectivity with chip via Bus Pirate connected at ttyUSB0
$ avrdude -c buspirate -P /dev/ttyUSB0 -p t85 Attempting to initiate BusPirate binary mode... avrdude: Paged flash write enabled. avrdude: AVR device initialized and ready to accept instructions Reading | ################################################## | 100% 0.09s avrdude: Device signature = 0x1e930b (probably t85) avrdude: safemode: Fuses OK (E:FF, H:DF, L:62) avrdude done. Thank you.
Write file "t85_default.hex" to ATtiny85
$ avrdude -c buspirate -P /dev/ttyUSB0 -p t85 -U flash:w:t85_default.hex
Attempting to initiate BusPirate binary mode...
avrdude: Paged flash write enabled.
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.09s
avrdude: Device signature = 0x1e930b (probably t85)
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "t85_default.hex"
avrdude: input file t85_default.hex auto detected as Intel Hex
avrdude: writing flash (8124 bytes):
Writing | ################################################## | 100% 0.00s
avrdude: 8124 bytes of flash written
avrdude: verifying flash memory against t85_default.hex:
avrdude: load data flash data from input file t85_default.hex:
avrdude: input file t85_default.hex auto detected as Intel Hex
avrdude: input file t85_default.hex contains 8124 bytes
avrdude: reading on-chip flash data:
Reading | ################################################## | 100% 51.02s
avrdude: verifying ...
avrdude: 8124 bytes of flash verified
avrdude: safemode: Fuses OK (E:FF, H:DF, L:62)
avrdude done. Thank you.
Burn fuses
$ avrdude -c buspirate -P /dev/ttyUSB0 -p t85 -U lfuse:w:0xe1:m -U hfuse:w:0xdd:m -U efuse:w:0xfe:m -B 20 Attempting to initiate BusPirate binary mode... avrdude: Paged flash write enabled. avrdude: AVR device initialized and ready to accept instructions Reading | ################################################## | 100% 0.01s avrdude: Device signature = 0x1e930b (probably t85) avrdude: reading input file "0xe1" avrdude: writing lfuse (1 bytes): Writing | ################################################## | 100% 0.01s avrdude: 1 bytes of lfuse written avrdude: verifying lfuse memory against 0xe1: avrdude: load data lfuse data from input file 0xe1: avrdude: input file 0xe1 contains 1 bytes avrdude: reading on-chip lfuse data: Reading | ################################################## | 100% 0.00s avrdude: verifying ... avrdude: 1 bytes of lfuse verified avrdude: reading input file "0xdd" avrdude: writing hfuse (1 bytes): Writing | ################################################## | 100% 0.01s avrdude: 1 bytes of hfuse written avrdude: verifying hfuse memory against 0xdd: avrdude: load data hfuse data from input file 0xdd: avrdude: input file 0xdd contains 1 bytes avrdude: reading on-chip hfuse data: Reading | ################################################## | 100% 0.00s avrdude: verifying ... avrdude: 1 bytes of hfuse verified avrdude: reading input file "0xfe" avrdude: writing efuse (1 bytes): Writing | ################################################## | 100% 0.01s avrdude: 1 bytes of efuse written avrdude: verifying efuse memory against 0xfe: avrdude: load data efuse data from input file 0xfe: avrdude: input file 0xfe contains 1 bytes avrdude: reading on-chip efuse data: Reading | ################################################## | 100% 0.00s avrdude: verifying ... avrdude: 1 bytes of efuse verified avrdude: safemode: Fuses OK (E:FE, H:DD, L:E1) avrdude done. Thank yo
Additional Resources:
Prior work that lead up to micronucleus development http://www.embedded-creations.com/projects/attiny85-usb-bootloader-overview/details
More details, variations on using Bus Pirate for flashing bootloader http://hintshop.ludvig.co.nz/show/buspirate-avr-programming/
Some notes on using Bus Pirate with Arch linux https://wiki.archlinux.org/index.php/Bus_pirate
The avrdude project http://savannah.nongnu.org/projects/avrdude
Datasheet[edit]
Schematics[edit]
Digispark using 5v chip supply and "level shifting" diodes on data lines
Adafruit Gemma using 3.3v regulator and no diodes
Threads on USB data line voltages and series/terminator resistor:
- https://electronics.stackexchange.com/questions/190592/why-does-usb-have-vcc-5v-and-high-3-3v
- http://www.eevblog.com/forum/projects/why-usb-data-series-resistors/
Purchase[edit]
- https://www.digikey.com/product-detail/en/microchip-technology/ATTINY85-20PU/ATTINY85-20PU-ND
- http://www.mouser.com/ProductDetail/Microchip-Technology-Atmel/ATtiny85-20PU
- https://www.sparkfun.com/products/9378
DUMPS[edit]
Probing a factory fresh unprogrammed chip with a Bus Pirate per http://dangerousprototypes.com/docs/Bus_Pirate_AVR_ProgrammingChange note change to "-p t85" vs example provided.
$ avrdude -c buspirate -P /dev/ttyUSB0 -p t85 -v
avrdude: Version 6.3, compiled on Aug 9 2017 at 12:31:56
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch
System wide configuration file is "/etc/avrdude.conf"
User configuration file is "/home/neo/.avrduderc"
User configuration file does not exist or is not a regular file, skipping
Using Port : /dev/ttyUSB0
Using Programmer : buspirate
AVR Part : ATtiny85
Chip Erase delay : 4500 us
PAGEL : P00
BS2 : P00
RESET disposition : possible i/o
RETRY pulse : SCK
serial program mode : yes
parallel program mode : yes
Timeout : 200
StabDelay : 100
CmdexeDelay : 25
SyncLoops : 32
ByteDelay : 0
PollIndex : 3
PollValue : 0x53
Memory Detail :
Block Poll Page Polled
Memory Type Mode Delay Size Indx Paged Size Size #Pages MinW MaxW ReadBack
----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
eeprom 65 6 4 0 no 512 4 0 4000 4500 0xff 0xff
flash 65 6 32 0 yes 8192 64 128 4500 4500 0xff 0xff
signature 0 0 0 0 no 3 0 0 0 0 0x00 0x00
lock 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
lfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
hfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
efuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
calibration 0 0 0 0 no 1 0 0 0 0 0x00 0x00
Programmer Type : BusPirate
Description : The Bus Pirate
Attempting to initiate BusPirate binary mode...
BusPirate binmode version: 1
BusPirate SPI version: 1
avrdude: Paged flash write enabled.
AVR Extended Commands not found.
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.09s
avrdude: Device signature = 0x1e930b (probably t85)
avrdude: safemode: hfuse reads as DF
avrdude: safemode: efuse reads as FF
avrdude: safemode: hfuse reads as DF
avrdude: safemode: efuse reads as FF
avrdude: safemode: Fuses OK (E:FF, H:DF, L:62)
BusPirate is back in the text mode
avrdude done. Thank you.
\/ Erronious dumps returning not exactly expected results \/
Probing with a Bus Pirate, and NO CHIP CONNECTED
$ avrdude -c buspirate -P /dev/ttyUSB0 -p attiny2313 -v
avrdude: Version 6.3, compiled on Aug 9 2017 at 12:31:56
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch
System wide configuration file is "/etc/avrdude.conf"
User configuration file is "/home/neo/.avrduderc"
User configuration file does not exist or is not a regular file, skipping
Using Port : /dev/ttyUSB0
Using Programmer : buspirate
AVR Part : ATtiny2313
Chip Erase delay : 9000 us
PAGEL : PD4
BS2 : PD6
RESET disposition : possible i/o
RETRY pulse : SCK
serial program mode : yes
parallel program mode : yes
Timeout : 200
StabDelay : 100
CmdexeDelay : 25
SyncLoops : 32
ByteDelay : 0
PollIndex : 3
PollValue : 0x53
Memory Detail :
Block Poll Page Polled
Memory Type Mode Delay Size Indx Paged Size Size #Pages MinW MaxW ReadBack
----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
eeprom 65 6 4 0 no 128 4 0 4000 4500 0xff 0xff
flash 65 6 32 0 yes 2048 32 64 4500 4500 0xff 0xff
signature 0 0 0 0 no 3 0 0 0 0 0x00 0x00
lock 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
lfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
hfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
efuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
calibration 0 0 0 0 no 2 0 0 0 0 0x00 0x00
Programmer Type : BusPirate
Description : The Bus Pirate
Attempting to initiate BusPirate binary mode...
BusPirate binmode version: 1
BusPirate SPI version: 1
avrdude: Paged flash write enabled.
AVR Extended Commands not found.
avrdude: initialization failed, rc=-2
Double check connections and try again, or use -F to override
this check.
BusPirate is back in the text mode
avrdude done. Thank you.
Probing with chip connected, and using wrong partno (-p attiny2313) per default example.
$ avrdude -c buspirate -P /dev/ttyUSB0 -p attiny2313 -v
avrdude: Version 6.3, compiled on Aug 9 2017 at 12:31:56
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch
System wide configuration file is "/etc/avrdude.conf"
User configuration file is "/home/neo/.avrduderc"
User configuration file does not exist or is not a regular file, skipping
Using Port : /dev/ttyUSB0
Using Programmer : buspirate
AVR Part : ATtiny2313
Chip Erase delay : 9000 us
PAGEL : PD4
BS2 : PD6
RESET disposition : possible i/o
RETRY pulse : SCK
serial program mode : yes
parallel program mode : yes
Timeout : 200
StabDelay : 100
CmdexeDelay : 25
SyncLoops : 32
ByteDelay : 0
PollIndex : 3
PollValue : 0x53
Memory Detail :
Block Poll Page Polled
Memory Type Mode Delay Size Indx Paged Size Size #Pages MinW MaxW ReadBack
----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
eeprom 65 6 4 0 no 128 4 0 4000 4500 0xff 0xff
flash 65 6 32 0 yes 2048 32 64 4500 4500 0xff 0xff
signature 0 0 0 0 no 3 0 0 0 0 0x00 0x00
lock 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
lfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
hfuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
efuse 0 0 0 0 no 1 0 0 9000 9000 0x00 0x00
calibration 0 0 0 0 no 2 0 0 0 0 0x00 0x00
Programmer Type : BusPirate
Description : The Bus Pirate
Attempting to initiate BusPirate binary mode...
BusPirate binmode version: 1
BusPirate SPI version: 1
avrdude: Paged flash write enabled.
AVR Extended Commands not found.
avrdude: AVR device initialized and ready to accept instructions
Reading | ################################################## | 100% 0.09s
avrdude: Device signature = 0x1e930b (probably t85)
avrdude: Expected signature for ATtiny2313 is 1E 91 0A
Double check chip, or use -F to override this check.
BusPirate is back in the text mode
avrdude done. Thank you.