Age | Commit message (Collapse) | Author |
|
Assume a maximum memory capacity, currently open coded, could become a
user servicable option when needed. Automatically flush the accumulated
outgoing data when a memory read reaches address 256.
Drop the unconditional START condition check now that it became obsolete.
|
|
The protocol is clocked, so strictly does not depend on the samplerate.
When the samplerate is available, the duration of internal processing
(memory erase and write) can get annotated. It's an optional feature.
The datasheet suggests that write and erase time are in the range of a
few milliseconds. Normalize to ms units and provide 10us resolution.
|
|
Rephrase how the decoder's progress during data interpretation gets
tracked. Extend the set of .wait() conditions in the main loop, and
determine START/STOP conditions and BIT validity there already, which
reduces redundancy with called handlers.
Increase the decoder's coverage of the memory card's feature set and
constraints. Handle the optional CLK during RST, to tell interrupted
memory access from card reset. Interpret known command codes, to present
their meaning and arguments to users, and to tell "outgoing data" (the
card's memory content) from "internal processing" (providing clock until
the card signals completion of a write access). Get initial statistics
on internal processing (clock count, and terminal I/O level, no duration
in units of wall clock time yet).
Unfortunately there is no reliable condition to detect the end of a
memory read when it executes to the end of the memory card's capacity.
That's why START detection is more greedy than specified, to reliably
re-sync to subsequent commands and their byte sequences.
Arrange for an improved set of annotation rows with symbols (bit level),
fields (data bytes), and operations details (summary of memory access
including protection).
Rename the binary output. It carries "any bytes" which were seen, the
command bytes as well as response data bytes.
|
|
Coupling the logic which interprets input signals at different levels
and the helpers which emit annotations by means of "global" variables
(public members of the decoder object) is unfortunate. It complicates
the logic, adds unnecessary dependencies, and makes maintenance rather
tedious and error prone.
Pass ss/es times to put() routines the same way as annotation classes
and annotation texts are passed. This simplifies the logic where bits
and bytes levels and additional rows are handled. The data values and
their spans all become local information that gets determined in the
same context. Which dramatically simplifies review.
|
|
These are just nits, behaviour remains. The comment may be incorrect
how command and data modes are detected. Add a developer comment for
later revisit. Drop unneeded parentheses in a ternary operation, and
move an ATR related comment around.
|
|
The decoder cannot know the state of the input signal before the start
of the capture. Assuming the RESET state results in incorrect output for
data bits which we don't know the context of. Start from unknown state
instead until a reliable condition is seen to synchronize to.
|
|
The 'databyte' is strictly local to the routine when 8 bits were seen.
The 'bitcount' is redundant and becomes obsolete when bits[] is a Python
list. The comment and the code disagreed, the wire is said to communicate
bits in LSB first order, the implemenation kept accumulating bits in the
reverse order (the annotation part, not the data byte math). Prefer the
common helper to convert bits to bytes.
There is uncertainty about the bit width "estimation" logic. The main
loop's .wait() conditions suggest that data bit values are valid for the
period of high CLK, which provides an easier and more robust condition
for annotation boundaries. Add a comment for now. The order of bit and
byte values' annotation emission is unfortunate, too.
|
|
Concentrate all text variants for zoom levels in a single spot. Remove
duplicates, and on the other hand add more verbose phrases to support
users which are not intimately familiar with the protocol. Prefer the
Python strings .format() method over the % operator for its versatility
and readability.
|
|
Eliminate magic numbers for annotation classes, prefer symbolic names
instead to improve readability. Put the annotation classes in an order
which matches the annotation rows' order. Reduce indentation in the
'proto' table while we are here (yet keep the vertical alignment).
|
|
Eliminate magic numbers for input pins and signal transition conditions.
Which dramatically improves readability and simplifies review.
|
|
The current implementation exclusively communicated the 'RESET'
condition but nothing else. Remove the Python output from the decoder,
it's easy to re-introduce when a complete implementation materializes.
There also is no known recipient of SLE44xx Python output right now
which would expect to see even the currently implemented subset.
|
|
Add a stronger hint to "memory cards", users might expect to see this
detail in the decoder's description. Rephrase how the reset line will
terminate pending memory reads.
|
|
The decoder was created in an older setup and would not load in recent
applications. Add missing boilerplate which is mandatory. Rename 'data'
since annotation classes and rows must not have ambiguous names, and
there is no singular form of 'data' -- use 'fields' instead. This also
fixes a missing line termination at the end of the text file.
|
|
Introduce an initial implementation of the SLE44xx protocol decoder for
Siemens/Infineon SLE 4418/28/32/42 memory cards. ATR (Answer To Reset),
command and data bytes get displayed, and RESET/abort events are marked.
Extracted data bytes are made available as binary output.
|