NAME
Device::Chip::AVR_HVSP - high-voltage serial programming for AVR chips
DESCRIPTION
This Device::Chip subclass allows interaction with an AVR
microcontroller of the ATtiny family in high-voltage serial programming
(HVSP) mode. It is particularly useful for configuring fuses or working
with a chip with the RSTDISBL fuse programmed, because in such cases a
regular ISP programmer cannot be used.
CONNECTIONS
To use this module you will need to make connections to the pins of the
ATtiny chip:
ATtiny | tiny84 | tiny85
-------+--------+-------
SDO | 9 | 7
SII | 8 | 6
SDI | 7 | 5
SCI | 2 | 2
RESET | 4 | 1
Vcc | 1 | 8
GND | 14 | 4
This module recognises the following kinds of adapter and automatically
assigns default pin connections for likely configurations:
Bus Pirate | Sparkfun | Seeed |:| ATtiny
| cable | cable |:|
-----------+----------+----------+-+-------
MISO | brown | black |:| SDO
CS | red | white |:| SII
MOSI | orange | grey |:| SDI
CLK | yellow | purple |:| SCI
AUX | green | blue |:| HV control
+5V | grey | orange |:| Vcc
GND | black | brown |:| GND
FTDI |:| ATtiny
-----+-+-------
D0 |:| SCI
D1 |:| SDI
D2 |:| SDO
D3 |:| SII
D4 |:| HV control
For other kinds of adapter, use the named parameters to the "mount"
method to tell the chip driver which ATtiny pin is connected to what
GPIO line.
The HV control line from the adapter will need to be able to control a
+12V supply to the RESET pin of the ATtiny chip. It should be
active-high, and can be achieved by a two-stage NPN-then-PNP transistor
arrangement.
Additionally, the SDO pin and the PA0 to PA2 pins of 14-pin devices
will need a pull-down to ground of around 100Ohm to 1kOhm.
MOUNT PARAMETERS
sdi, sii, sci, sdo
The names of GPIO lines on the adapter that are connected to the HVSP
signal pins of the ATtiny chip.
hv
The name of the GPIO line on the adapter that is connected to the 12V
power supply control.
METHODS
The following methods documented with a trailing call to ->get return
Future instances.
$chip->start->get
Powers up the device, reads and checks the signature, ensuring it is a
recognised chip.
This method leaves the chip powered up with +5V on Vcc and +12V on
RESET. Use the power, hv_power or all_power methods to turn these off
if it is not required again immediately.
$chip->stop->get
Shut down power to the device.
$chip->power( $on )->get
Controls +5V to the Vcc pin of the ATtiny chip.
$chip->hv_power( $on )->get
Controls +12V to the RESET pin of the ATtiny chip.
$chip->all_power( $on )->get
Controls both +5V and +12V supplies at once. The +12V supply is turned
on last but off first, ensuring the correct HVSP-RESET sequence is
applied to the chip.
$name = $chip->partname
Returns the name of the chip whose signature was detected by the start
method.
$memory = $avr->memory_info( $name )
Returns a memory info structure giving details about the named memory
for the attached part. The following memory names are recognised:
signature calibration lock lfuse hfuse efuse flash eeprom
(Note that the ATtiny13 has no efuse memory).
The structure will respond to the following methods:
* wordsize
Returns number of bits per word. This will be 8 for the byte-oriented
memories, but 16 for the main program flash.
* pagesize
Returns the number of words per page; the smallest amount that can be
written in one go.
* words
Returns the total number of words that are available.
* can_write
Returns true if the memory type can be written (in general; this does
not take into account the lock bits that might futher restrict a
particular chip).
%memories = $avr->memory_infos
Returns a key/value list of all the known device memories.
$fuseinfo = $avr->fuseinfo
Returns a Device::Chip::AVR_HVSP::FuseInfo instance containing
information on the fuses in the attached device type.
$avr->chip_erase->get
Performs an entire chip erase. This will clear the flash and EEPROM
memories, before resetting the lock bits. It does not affect the fuses.
$bytes = $avr->read_signature->get
Reads the three device signature bytes and returns them in as a single
binary string.
$byte = $avr->read_calibration->get
Reads the calibration byte.
$byte = $avr->read_lock->get
Reads the lock byte.
$avr->write_lock( $byte )->get
Writes the lock byte.
$int = $avr->read_fuse_byte( $fuse )->get
Reads one of the fuse bytes lfuse, hfuse, efuse, returning an integer.
$avr->write_fuse_byte( $fuse, $byte )->get
Writes one of the fuse bytes lfuse, hfuse, efuse from an integer.
$byte = $avr->read_lfuse->get
$byte = $avr->read_hfuse->get
$byte = $avr->read_efuse->get
Convenient shortcuts to reading the low, high and extended fuses
directly, returning a byte.
$avr->write_lfuse( $byte )->get
$avr->write_hfuse( $byte )->get
$avr->write_efuse( $byte )->get
Convenient shortcuts for writing the low, high and extended fuses
directly, from a byte.
$bytes = $avr->read_flash( %args )->get
Reads a range of the flash memory and returns it as a binary string.
Takes the following optional arguments:
start => INT
stop => INT
Address range to read. If omitted, reads the entire memory.
bytes => INT
Alternative to stop; gives the nubmer of bytes (i.e. not words of
flash) to read.
$avr->write_flash( $bytes )->get
Writes the flash memory from the binary string.
$bytes = $avr->read_eeprom( %args )->get
Reads a range of the EEPROM memory and returns it as a binary string.
Takes the following optional arguments:
start => INT
stop => INT
Address range to read. If omitted, reads the entire memory.
bytes => INT
Alternative to stop; gives the nubmer of bytes to read.
$avr->write_eeprom( $bytes )->get
Writes the EEPROM memory from the binary string.
SEE ALSO
*
http://dangerousprototypes.com/2014/10/27/high-voltage-serial-programming-for-avr-chips-with-the-bus-pirate/
- High voltage serial programming for AVR chips with the Bus Pirate.
AUTHOR
Paul Evans <
[email protected]>
