|
|
| (2 intermediate revisions by one other user not shown) |
| Line 1: |
Line 1: |
| [[File:Buspirate v3 front.jpg|thumb|right|<small>Bus Pirate v3, front</small>]]
| | {{#externalredirect: https://www.flashrom.org/supported_hw/supported_prog/buspirate.html }} |
| [[File:Buspirate v3 back.jpg|thumb|right|<small>Bus Pirate v3, back</small>]]
| |
| [[File:Lycom-pe115-flashrom-buspirate-2.jpg|thumb|right|<small>Recovering a bricked SPI based device using a Bus Pirate</small>]]
| |
| | |
| The [http://dangerousprototypes.com/docs/Bus_Pirate Bus Pirate] is an open source design for a multi-purpose chip-level serial protocol transceiver and debugger. Flashrom supports the Bus Pirate for [http://dangerousprototypes.com/docs/SPI SPI programming]. It also has [http://dangerousprototypes.com/docs/Bus_Pirate_binary_SPI_sniffer_utility SPI sniffing] functionality, which may come in useful for analysing chip or programmer behaviour.
| |
| | |
| They are available for around US$30 from various sources.
| |
| | |
| ==Connections==
| |
| The table below shows how a typical SPI flash chip (sitting in the center of the table) needs to be connected (NB: not all flash chips feature all of the pins below, but in general you should always connect all input pins of ICs to some defined potential (usually GND or VCC), ideally with a pull-up/down resistor in between). Most SPI flash chips require a 3.3V supply voltage, but there exist some models that use e.g. 1.8V. Make sure the device in question is compatible before connecting any wires.
| |
| | |
| {| style="border-collapse: collapse; border: 1px solid black;" cellpadding="5"; border="1" align="center" | |
| ! Description
| |
| ! Bus Pirate
| |
| ! Dir.
| |
| ! colspan="4"|Flash chip
| |
| ! Dir.
| |
| ! Bus Pirate
| |
| ! Description
| |
| |-
| |
| | align="right" | (not) Chip Select || CS || <font size="+2">→</font> || style="background: #DDDDDD;" | 1 || align="left" style="background: #DDDDDD;" | /CS || align="right" style="background: #DDDDDD;" | VCC || style="background: #DDDDDD;" | 8 || <font size="+2">←</font> || +3.3v || align="left" | Supply
| |
| |-
| |
| | align="right" | Master In, Slave Out || MISO || <font size="+2">←</font> || style="background: #DDDDDD;" | 2 || align="left" style="background: #DDDDDD;" | DO (IO1) || align="right" style="background: #DDDDDD;" | /HOLD (IO3) || style="background: #DDDDDD;" | 7 || <font size="+2">←</font> || +3.3v || align="left" | (not) hold (see datasheets)
| |
| |-
| |
| | align="right" | (not) Write Protect || +3.3v || <font size="+2">→</font> || style="background: #DDDDDD;" | 3 || align="left" style="background: #DDDDDD;" | /WP (IO2) || align="right" style="background: #DDDDDD;" | CLK || style="background: #DDDDDD;" | 6 || <font size="+2">←</font> || SCLK || align="left" | The SPI clock
| |
| |-
| |
| | align="right" | Ground || GND || <font size="+2">→</font> || style="background: #DDDDDD;" | 4 || align="left" style="background: #DDDDDD;" | GND || align="right" style="background: #DDDDDD;" | DI (IO0) || style="background: #DDDDDD;" | 5 || <font size="+2">←</font> || MOSI || align="left" | Master Out, Slave In
| |
| |-
| |
| |}
| |
| | |
| == Usage ==
| |
| | |
| $ '''flashrom -p buspirate_spi:dev=''/dev/device'',spispeed=''frequency'' '''
| |
| | |
| Example:
| |
| | |
| $ '''flashrom -p buspirate_spi:dev=/dev/ttyUSB0,spispeed=1M'''
| |
| | |
| == Troubleshooting ==
| |
| | |
| In case of problems probing the chip with flashrom - especially when connecting chips still soldered in a system - please take a look at [[ISP|this page]].
| |
| In circuit programming it often possible, '''so long as no other devices on the SPI bus are trying to access the device'''.
| |
| | |
| == Speedup ==
| |
| A beta firmware build exists, to speed up the buspirate. See this post on dangerousprototypes.com:
| |
| http://dangerousprototypes.com/forum/viewtopic.php?f=40&t=3864&start=15#p41505
| |
| | |
| http://dangerousprototypes.com/docs/Bus_Pirate#Firmware_upgrades
| |