diff options
Diffstat (limited to 'decoders/onewire_link')
| -rw-r--r-- | decoders/onewire_link/__init__.py | 33 | ||||
| -rw-r--r-- | decoders/onewire_link/onewire_link.py | 2 |
2 files changed, 20 insertions, 15 deletions
diff --git a/decoders/onewire_link/__init__.py b/decoders/onewire_link/__init__.py index 6eaeadd..c2e38d3 100644 --- a/decoders/onewire_link/__init__.py +++ b/decoders/onewire_link/__init__.py @@ -23,11 +23,12 @@ 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: +layered. - 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. +- Network layer (skip/search/match device ROM addresses) +- Transport layer (transfer data between 1-Wire master and device) + +Link layer Sample rate: A high enough sample rate is required to properly detect all the elements of @@ -50,27 +51,31 @@ 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. 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. +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. TODO: -- add CRC checks for network layer -- add transport layer code -- review link layer code, to check for protocol correctness -- define output protocol +- check for protocol correctness, if events are timed inside prescribed limits +- maybe add support for interrupts, check if this feature is deprecated ''' from .onewire_link import * diff --git a/decoders/onewire_link/onewire_link.py b/decoders/onewire_link/onewire_link.py index ab73b6f..f4b7b30 100644 --- a/decoders/onewire_link/onewire_link.py +++ b/decoders/onewire_link/onewire_link.py @@ -38,7 +38,7 @@ class Decoder(srd.Decoder): {'id': 'pwr', 'name': 'PWR', 'desc': '1-Wire power'}, ] options = { - 'overdrive' : ['Overdrive', 1], + 'overdrive' : ['Overdrive', 1], 'cnt_normal_bit' : ['Time (in samplerate periods) for normal mode sample bit' , 0], 'cnt_normal_slot' : ['Time (in samplerate periods) for normal mode data slot' , 0], 'cnt_normal_presence' : ['Time (in samplerate periods) for normal mode sample presence', 0], |