onewire: updated documentation

2 files changed, 22 insertions, 41 deletions

diff --git a/decoders/onewire_transport/__init__.py b/decoders/onewire_transport/__init__.py
index 28db017..3b9577e 100644
--- a/decoders/onewire_transport/__init__.py
+++ b/decoders/onewire_transport/__init__.py
@@ -23,54 +23,34 @@
 
 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)
 
-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
+Transport layer
 
-Probes:
-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)
-
-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,
-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.
+The transport layer is the largest and most complex part of the protocol, since
+it is very device specific. The decoder is parsing only a small part of the
+protocol.
 
 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.
+The next link layer annotations are shown:
+- 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.
+The next network layer annotations are shown:
+- ROM val
+  The 64bit value of the addressed device is displayed:
+  family code (1B) + serial number (6B) + CRC (1B)
+- FUNCTION COMMAND val name
+  The requested FUNCTION command is displayed as an 8bit HEX value and by name.
+- DATA val
+  Data intended for the transport layer is displayed as an 8bit HEX value.
 
 TODO:
-- add CRC checks for network layer
-- add transport layer code
-- review link layer code, to check for protocol correctness
-- define output protocol
+- add CRC checks for transport layer
 '''
 
 from .onewire_transport import *
diff --git a/decoders/onewire_transport/onewire_transport.py b/decoders/onewire_transport/onewire_transport.py
index bc9efbb..67f5193 100644
--- a/decoders/onewire_transport/onewire_transport.py
+++ b/decoders/onewire_transport/onewire_transport.py
@@ -22,6 +22,7 @@
 
 import sigrokdecode as srd
 
+# a dictionary of FUNCTION commands and their names
 command = {0x44: "TEMPERATURE CONVERSION",
            0xbe: "READ SCRATCHPAD"}