X-Git-Url: https://sigrok.org/gitweb/?p=libsigrokdecode.git;a=blobdiff_plain;f=decoders%2Fonewire_link%2F__init__.py;h=28b0194bb324796e6534d531659d255f4339d36a;hp=6eaeadd047aecb68a781a34feae28f350bb5541a;hb=4539e9ca58966ce3c9cad4801b16c315e86ace01;hpb=99f5f3b5ac31347795582872a5d92f3d9430c21d diff --git a/decoders/onewire_link/__init__.py b/decoders/onewire_link/__init__.py index 6eaeadd..28b0194 100644 --- a/decoders/onewire_link/__init__.py +++ b/decoders/onewire_link/__init__.py @@ -1,5 +1,5 @@ ## -## This file is part of the sigrok project. +## This file is part of the libsigrokdecode project. ## ## Copyright (C) 2012 Uwe Hermann ## @@ -14,63 +14,54 @@ ## 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 . ## ''' -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, the provided parser decodes the next layers: -- Link layer (reset, presence detection, reading/writing bits) -- Network layer (skip, search, match device ROM addresses) -The higher layers (transport, presentation) are not decoded, since they are -mostly device specific and it would take a lot of code to interpret them. +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) 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: + + - overdrive available: 2MHz minimum, 5MHz suggested + - overdrive not available: 400kHz minimum, 1MHz suggested -Probes: +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_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_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: -Annotations can be shown for each layer of the protocol separately: -- link (the value of each transmitted bit is shown separately) -- network (the ROM command, and address are shown) -- transport (only transport layer byte transfers are shown) -If link layer annotations are shown, possible issues with sample rate and sample -timing are also shown. + - 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: -- add CRC checks for network layer -- add transport layer code -- review link layer code, to check for protocol correctness -- define output protocol +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