diff options
Diffstat (limited to 'decoders/uart/uart.py')
| -rw-r--r-- | decoders/uart/uart.py | 45 |
1 files changed, 14 insertions, 31 deletions
diff --git a/decoders/uart/uart.py b/decoders/uart/uart.py index 4ceaef6..1604834 100644 --- a/decoders/uart/uart.py +++ b/decoders/uart/uart.py @@ -35,23 +35,6 @@ GET_STOP_BITS = 4 RX = 0 TX = 1 -# Parity options -PARITY_NONE = 0 -PARITY_ODD = 1 -PARITY_EVEN = 2 -PARITY_ZERO = 3 -PARITY_ONE = 4 - -# Stop bit options -STOP_BITS_0_5 = 0 -STOP_BITS_1 = 1 -STOP_BITS_1_5 = 2 -STOP_BITS_2 = 3 - -# Bit order options -LSB_FIRST = 0 -MSB_FIRST = 1 - # Annotation feed formats ANN_ASCII = 0 ANN_DEC = 1 @@ -62,22 +45,22 @@ ANN_BITS = 4 # Given a parity type to check (odd, even, zero, one), the value of the # parity bit, the value of the data, and the length of the data (5-9 bits, # usually 8 bits) return True if the parity is correct, False otherwise. -# PARITY_NONE is _not_ allowed as value for 'parity_type'. +# 'none' is _not_ allowed as value for 'parity_type'. def parity_ok(parity_type, parity_bit, data, num_data_bits): # Handle easy cases first (parity bit is always 1 or 0). - if parity_type == PARITY_ZERO: + if parity_type == 'zero': return parity_bit == 0 - elif parity_type == PARITY_ONE: + elif parity_type == 'one': return parity_bit == 1 # Count number of 1 (high) bits in the data (and the parity bit itself!). ones = bin(data).count('1') + parity_bit # Check for odd/even parity. - if parity_type == PARITY_ODD: + if parity_type == 'odd': return (ones % 2) == 1 - elif parity_type == PARITY_EVEN: + elif parity_type == 'even': return (ones % 2) == 0 else: raise Exception('Invalid parity type: %d' % parity_type) @@ -102,10 +85,10 @@ class Decoder(srd.Decoder): options = { 'baudrate': ['Baud rate', 115200], 'num_data_bits': ['Data bits', 8], # Valid: 5-9. - 'parity_type': ['Parity type', PARITY_NONE], - 'parity_check': ['Check parity?', True], # TODO: Bool supported? - 'num_stop_bits': ['Stop bit(s)', STOP_BITS_1], - 'bit_order': ['Bit order', LSB_FIRST], + 'parity_type': ['Parity type', 'none'], + 'parity_check': ['Check parity?', 'yes'], # TODO: Bool supported? + 'num_stop_bits': ['Stop bit(s)', '1'], # String! 0, 0.5, 1, 1.5. + 'bit_order': ['Bit order', 'lsb-first'], # TODO: Options to invert the signal(s). } annotations = [ @@ -208,15 +191,15 @@ class Decoder(srd.Decoder): self.startsample[rxtx] = self.samplenum # Get the next data bit in LSB-first or MSB-first fashion. - if self.options['bit_order'] == LSB_FIRST: + if self.options['bit_order'] == 'lsb-first': self.databyte[rxtx] >>= 1 self.databyte[rxtx] |= \ (signal << (self.options['num_data_bits'] - 1)) - elif self.options['bit_order'] == MSB_FIRST: + elif self.options['bit_order'] == 'msb-first': self.databyte[rxtx] <<= 1 self.databyte[rxtx] |= (signal << 0) else: - raise Exception('Invalid bit order value: %d', + raise Exception('Invalid bit order value: %s', self.options['bit_order']) # Return here, unless we already received all data bits. @@ -242,7 +225,7 @@ class Decoder(srd.Decoder): def get_parity_bit(self, rxtx, signal): # If no parity is used/configured, skip to the next state immediately. - if self.options['parity_type'] == PARITY_NONE: + if self.options['parity_type'] == 'none': self.state[rxtx] = GET_STOP_BITS return @@ -272,7 +255,7 @@ class Decoder(srd.Decoder): # TODO: Currently only supports 1 stop bit. def get_stop_bits(self, rxtx, signal): # Skip samples until we're in the middle of the stop bit(s). - skip_parity = 0 if self.options['parity_type'] == PARITY_NONE else 1 + skip_parity = 0 if self.options['parity_type'] == 'none' else 1 b = self.options['num_data_bits'] + 1 + skip_parity if not self.reached_bit(rxtx, b): return |