nrf24l01: Don't decode incomplete commands.

[libsigrokdecode.git] / decoders / nrf24l01 / pd.py

diff --git a/decoders/nrf24l01/pd.py b/decoders/nrf24l01/pd.py
index 3208a200e1625f639ca0f24534ee3174fa3df007..38e5ac6b09e093d90bc6bfc52a1b6d00c7fc1a99 100644 (file)
--- a/decoders/nrf24l01/pd.py
+++ b/decoders/nrf24l01/pd.py
@@ -20,7 +20,7 @@
 
 import sigrokdecode as srd
 
-class MissingDataError(Exception):
+class ChannelError(Exception):
     pass
 
 regs = {
@@ -86,6 +86,8 @@ class Decoder(srd.Decoder):
 
     def __init__(self, **kwargs):
         self.next()
+        self.requirements_met = True
+        self.cs_was_released = False
 
     def start(self):
         self.out_ann = self.register(srd.OUTPUT_ANN)
@@ -144,9 +146,9 @@ class Decoder(srd.Decoder):
         '''Returns the label for the current command.'''
         if self.cmd == 'R_REGISTER':
             reg = regs[self.dat][0] if self.dat in regs else 'unknown register'
-            return 'Cmd. R_REGISTER "{}"'.format(reg)
+            return 'Cmd R_REGISTER "{}"'.format(reg)
         else:
-            return 'Cmd. {}'.format(self.cmd)
+            return 'Cmd {}'.format(self.cmd)
 
     def parse_command(self, b):
         '''Parses the command byte.
@@ -211,20 +213,25 @@ class Decoder(srd.Decoder):
             # The 'W_REGISTER' command is merged with the following byte(s).
             label = '{}: {}'.format(self.format_command(), name)
         else:
-            label = 'Reg. {}'.format(name)
+            label = 'Reg {}'.format(name)
 
-        self.decode_mb_data(pos, ann, data, label)
+        self.decode_mb_data(pos, ann, data, label, True)
 
-    def decode_mb_data(self, pos, ann, data, label, escape_all=True):
+    def decode_mb_data(self, pos, ann, data, label, always_hex):
         '''Decodes the data bytes 'data' of a multibyte command at position
-        'pos'. The decoded data is prefixed with 'label'. If 'excape_all' is
-        True, all data bytes are escaped as hex codes.'''
+        'pos'. The decoded data is prefixed with 'label'. If 'always_hex' is
+        True, all bytes are decoded as hex codes, otherwise only non
+        printable characters are escaped.'''
 
-        def escape(b):
-            c = chr(b)
-            if escape_all or not str.isprintable(c):
-                return '\\x{:02X}'.format(b)
-            return c
+        if always_hex:
+            def escape(b):
+                return '{:02X}'.format(b)
+        else:
+            def escape(b):
+                c = chr(b)
+                if not str.isprintable(c):
+                    return '\\x{:02X}'.format(b)
+                return c
 
         data = ''.join([escape(b) for b in data])
         text = '{} = "{}"'.format(label, data)
@@ -259,9 +266,19 @@ class Decoder(srd.Decoder):
                 self.warn(pos, 'wrong data for "ACTIVATE" command')
 
     def decode(self, ss, es, data):
+        if not self.requirements_met:
+            return
+
         ptype, data1, data2 = data
 
         if ptype == 'CS-CHANGE':
+            if data1 == -1:
+                if data2 == -1:
+                    self.requirements_met = False
+                    raise ChannelError('CS# pin required.')
+                elif data2 == 1:
+                    self.cs_was_released = True
+
             if data1 == 0 and data2 == 1:
                 # Rising edge, the complete command is transmitted, process
                 # the bytes that were send after the command byte.
@@ -274,12 +291,14 @@ class Decoder(srd.Decoder):
                         self.finish_command((self.mb_s, self.mb_e))
 
                 self.next()
-        elif ptype == 'DATA':
+                self.cs_was_released = True
+        elif ptype == 'DATA' and self.cs_was_released:
             mosi, miso = data1, data2
             pos = (ss, es)
 
             if miso is None or mosi is None:
-                raise MissingDataError('Both MISO and MOSI pins required.')
+                self.requirements_met = False
+                raise ChannelError('Both MISO and MOSI pins required.')
 
             if self.first:
                 self.first = False