avr/avrdude
2
0
Fork 0
mirror of https://github.com/mariusgreuel/avrdude.git synced 2025-09-27 14:35:27 +00:00
Code Issues Projects Releases Wiki Activity

Implement debugWire programming support. Several limitations are

Browse Source 
imposed by debugWire itself, so effectively, only flash ROM can be
read and written.

Currently, the required changes to avrdude.conf.in are only present
for the ATtiny44.


git-svn-id: svn://svn.savannah.nongnu.org/avrdude/trunk/avrdude@688 81a1dc3b-b13d-400b-aceb-764788c761c2
This commit is contained in:
Joerg Wunsch
2006-11-20 23:23:37 +00:00
parent 432ee9035b
commit 9b9df3e773
9 changed files with 477 additions and 48 deletions
Download Patch File Download Diff File Expand all files Collapse all files

41
doc/avrdude.texi
View File

@@ -182,11 +182,12 @@ protocol is more sophisticated.
(The JTAG ICE mkII protocol can also be run on top of USB.)
Only the memory programming functionality of the JTAG ICE is supported
by AVRDUDE.
For the JTAG ICE mkII, both JTAG and ISP mode are supported.
For the JTAG ICE mkII, JTAG, debugWire and ISP mode are supported.
See below for the limitations of debugWire.
The AVR Dragon is supported in all modes (ISP, JTAG, HVSP, PP).
The AVR Dragon is supported in all modes (ISP, JTAG, HVSP, PP, debugWire).
(High-voltage programming is not yet supported.)
When used in JTAG mode, the AVR Dragon behaves similar to a
When used in JTAG and debugWire mode, the AVR Dragon behaves similar to a
JTAG ICE mkII, so all device-specific comments for that device
will apply as well.
When used in ISP mode, the AVR Dragon behaves similar to an
@@ -385,6 +386,8 @@ Brian Dean's Programmer,@*
Atmel Butterfly Development Board
@item @code{dt006} @tab
Dontronics DT006
@item @code{dragon_dw} @tab
AVR Dragon in debugWire mode
@item @code{dragon_hvsp} @tab
AVR Dragon in high-voltage serial programming mode
@item @code{dragon_isp} @tab
@@ -409,6 +412,8 @@ Atmel JTAG ICE mkII, running at 115200 Bd
@emph{Same as before.}
@item @code{jtag2isp} @tab
Atmel JTAG ICE mkII in ISP mode.
@item @code{jtag2dw} @tab
Atmel JTAG ICE mkII in debugWire mode.
@item @code{pavr} @tab
Jason Kyle's pAVR Serial Programmer
@item @code{picoweb} @tab
@@ -1927,6 +1932,36 @@ Solution: none at this time. The simplicity of the USBasp programmer
doesn't offer a method to distinguish multiple programmers that are
connected simultaneously, so effectively only one USBasp is supported.
@item
Problem: I cannot do @dots{} when the target is in debugWire mode.
Solution: debugWire mode imposes several limitations.
The debugWire protocol is Atmel's proprietary one-wire (plus ground)
protocol to allow an in-circuit emulation of the smaller AVR devices,
using the @var{/RESET} line.
DebugWire mode is initiated by activating the @var{DWEN}
fuse, and then power-cycling the target.
While this mode is mainly intented for debugging/emulation, it
also offers limited programming capabilities.
Effectively, the only memory area that can be read or programmed
in this mode is the flash ROM.
It is also possible to read out the signature.
All other memory areas cannot be accessed.
There is no
@emph{chip erase}
functionality in debugWire mode; instead, while reprogramming the
flash ROM, each flash ROM page is erased right before updating it.
This is done transparently by the JTAG ICE mkII (or AVR Dragon).
The only way back from debugWire mode is to initiate a special
sequence of commands to the JTAG ICE mkII (or AVR Dragon), so the
debugWire mode will be temporarily disabled, and the target can
be accessed using normal ISP programming.
This sequence is automatically initiated by using the JTAG ICE mkII
or AVR Dragon in ISP mode, when they detect that ISP mode cannot be
entered.
@end itemize