##
-## This file is part of the sigrok project.
+## This file is part of the libsigrokdecode project.
##
## Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de>
##
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
-## along with this program; if not, write to the Free Software
-## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+## along with this program; if not, see <http://www.gnu.org/licenses/>.
##
'''
-1-Wire protocol decoder.
+This protocol decoder handles the 1-Wire link layer.
-The 1-Wire protocol enables bidirectional communication over a single wire (and
-ground) between a single master and one or multiple slaves. The protocol is
-layered.
-- Link layer (reset, presence detection, reading/writing bits)
-- Network layer (skip/search/match device ROM addresses)
-- Transport layer (transport data between 1-Wire master and device)
+The 1-Wire protocol enables bidirectional communication over a single wire
+(and ground) between a single master and one or multiple slaves. The protocol
+is layered:
-Link layer
+ - Link layer (reset, presence detection, reading/writing bits)
+ - Network layer (skip/search/match device ROM addresses)
+ - Transport layer (transport data between 1-Wire master and device)
Sample rate:
-A high enough sample rate is required to properly detect all the elements of
-the protocol. A lower sample rate can be used if the master does not use
-overdrive communication speed. The next minimal values should be used:
-- overdrive available: 2MHz minimum, 5MHz suggested
-- overdrive not available: 400kHz minimum, 1MHz suggested
+A sufficiently high samplerate is required to properly detect all the elements
+of the protocol. A lower samplerate can be used if the master does not use
+overdrive communication speed. The following minimal values should be used:
-Probes:
+ - overdrive available: 2MHz minimum, 5MHz suggested
+ - overdrive not available: 400kHz minimum, 1MHz suggested
+
+Channels:
1-Wire requires a single signal, but some master implementations might have a
-separate signal use to deliver power to the bus during temperature conversion
-as an example. This power signal is currently not parsed.
-- owr (1-Wire bus)
-- pwr (1-Wire power)
+separate signal used to deliver power to the bus during temperature conversion
+as an example. This power signal is currently not used.
+
+ - owr (1-Wire signal line)
+ - pwr (optional, dedicated power supply pin)
Options:
-1-Wire is an asynchronous protocol, so the decoder must know the sample rate.
-The timing for sampling bits, presence and reset is calculated by the decoder,
+1-Wire is an asynchronous protocol, so the decoder must know the samplerate.
+The timing for sampling bits, presence, and reset is calculated by the decoder,
but in case the user wishes to use different values, it is possible to
-configure the next timing values (number of sample rate periods):
-- overdrive (if active the decoder will be prepared for overdrive)
-- cnt_normal_bit (time for normal mode sample bit)
-- cnt_normal_slot (time for normal mode data slot)
-- cnt_normal_presence (time for normal mode sample presence)
-- cnt_normal_reset (time for normal mode reset)
-- cnt_overdrive_bit (time for overdrive mode sample bit)
-- cnt_overdrive_slot (time for overdrive mode data slot)
-- cnt_overdrive_presence (time for overdrive mode sample presence)
-- cnt_overdrive_reset (time for overdrive mode reset)
-This options should be configured only on very rare cases and the user should
-read the decoder source code to understand them correctly.
+configure the following timing values (number of samplerate periods):
-Annotations:
-Link layer annotations show the next events:
-- NOTE/WARNING/ERROR
- Possible sample rate related timing issues are reported.
-- RESET/PRESENCE True/False
- The event is marked from the signal negative edge to the end of the reset
- high period. It is also reported if there are any devices attached to the
- bus.
-- BIT 0/1
- The event is marked from the signal negative edge to the end of the data
- slot. The value of each received bit is also provided.
+ - overdrive (if active the decoder will be prepared for overdrive)
+ - cnt_normal_bit (time for normal mode sample bit)
+ - cnt_normal_slot (time for normal mode data slot)
+ - cnt_normal_presence (time for normal mode sample presence)
+ - cnt_normal_reset (time for normal mode reset)
+ - cnt_overdrive_bit (time for overdrive mode sample bit)
+ - cnt_overdrive_slot (time for overdrive mode data slot)
+ - cnt_overdrive_presence (time for overdrive mode sample presence)
+ - cnt_overdrive_reset (time for overdrive mode reset)
-TODO:
-- check for protocol correctness, if events are timed inside prescribed limits
-- maybe add support for interrupts, check if this feature is deprecated
+These options should be configured only on very rare cases and the user should
+read the decoder source code to understand them correctly.
'''
-from .onewire_link import *
+from .pd import Decoder
projects / libsigrokdecode.git / blobdiff