##
## This file is part of the libsigrokdecode project.
##
-## Copyright (C) 2013 Uwe Hermann <uwe@hermann-uwe.de>
+## Copyright (C) 2013-2016 Uwe Hermann <uwe@hermann-uwe.de>
+## Copyright (C) 2016 Chris Dreher <chrisdreher@hotmail.com>
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
-## along with this program; if not, write to the Free Software
-## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+## along with this program; if not, see <http://www.gnu.org/licenses/>.
##
import sigrokdecode as srd
TX = 1
class Decoder(srd.Decoder):
- api_version = 1
+ api_version = 2
id = 'midi'
name = 'MIDI'
longname = 'Musical Instrument Digital Interface'
outputs = ['midi']
annotations = (
('text-verbose', 'Human-readable text (verbose)'),
+ ('text-sysreal-verbose', 'Human-readable SysReal text (verbose)'),
+ ('text-error', 'Human-readable Error text'),
+ )
+ annotation_rows = (
+ ('normal', 'Normal', (0, 2)),
+ ('sys-real', 'SysReal', (1,)),
)
- def __init__(self, **kwargs):
- self.cmd = []
+ def __init__(self):
self.state = 'IDLE'
+ self.status_byte = 0
+ self.explicit_status_byte = False
+ self.cmd = []
self.ss = None
self.es = None
self.ss_block = None
self.es_block = None
def start(self):
- # self.out_python = self.register(srd.OUTPUT_PYTHON)
self.out_ann = self.register(srd.OUTPUT_ANN)
def putx(self, data):
self.put(self.ss_block, self.es_block, self.out_ann, data)
- def handle_channel_msg_0x80(self):
+ def get_note_name(self, channel, note):
+ if channel != 10:
+ return chromatic_notes[note]
+ else:
+ return 'assuming ' + percussion_notes.get(note, 'undefined')
+
+ def check_for_garbage_flush(self, is_flushed):
+ if is_flushed:
+ if self.explicit_status_byte:
+ self.cmd.insert(0, self.status_byte)
+ self.handle_garbage_msg(None)
+
+ def soft_clear_status_byte(self):
+ self.explicit_status_byte = False
+
+ def hard_clear_status_byte(self):
+ self.status_byte = 0
+ self.explicit_status_byte = False
+
+ def set_status_byte(self, newbyte):
+ self.status_byte = newbyte
+ self.explicit_status_byte = True
+
+ def handle_channel_msg_0x80(self, is_flushed):
# Note off: 8n kk vv
# n = channel, kk = note, vv = velocity
c = self.cmd
- if len(c) < 3:
+ if len(c) < 2:
+ self.check_for_garbage_flush(is_flushed)
return
self.es_block = self.es
- msg, chan, note, velocity = c[0] & 0xf0, (c[0] & 0x0f) + 1, c[1], c[2]
- self.putx([0, ['Channel %d: %s (note = %d, velocity = %d)' % \
- (chan, status_bytes[msg], note, velocity)]])
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ note, velocity = c[0], c[1]
+ note_name = self.get_note_name(chan, note)
+ self.putx([0, ['Channel %d: %s (note = %d \'%s\', velocity = %d)' % \
+ (chan, status_bytes[msg][0], note, note_name, velocity),
+ 'ch %d: %s %d, velocity = %d' % \
+ (chan, status_bytes[msg][1], note, velocity),
+ '%d: %s %d, vel %d' % \
+ (chan, status_bytes[msg][2], note, velocity)]])
self.cmd, self.state = [], 'IDLE'
+ self.soft_clear_status_byte()
- def handle_channel_msg_0x90(self):
+ def handle_channel_msg_0x90(self, is_flushed):
# Note on: 9n kk vv
# n = channel, kk = note, vv = velocity
# If velocity == 0 that actually means 'note off', though.
c = self.cmd
- if len(c) < 3:
+ if len(c) < 2:
+ self.check_for_garbage_flush(is_flushed)
return
- self.es_block = self.ss
- msg, chan, note, velocity = c[0] & 0xf0, (c[0] & 0x0f) + 1, c[1], c[2]
- s = 'note off' if (velocity == 0) else status_bytes[msg]
- self.putx([0, ['Channel %d: %s (note = %d, velocity = %d)' % \
- (chan, s, note, velocity)]])
+ self.es_block = self.es
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ note, velocity = c[0], c[1]
+ s = status_bytes[0x80] if (velocity == 0) else status_bytes[msg]
+ note_name = self.get_note_name(chan, note)
+ self.putx([0, ['Channel %d: %s (note = %d \'%s\', velocity = %d)' % \
+ (chan, s[0], note, note_name, velocity),
+ 'ch %d: %s %d, velocity = %d' % \
+ (chan, s[1], note, velocity),
+ '%d: %s %d, vel %d' % \
+ (chan, s[2], note, velocity)]])
self.cmd, self.state = [], 'IDLE'
+ self.soft_clear_status_byte()
- def handle_channel_msg_0xa0(self):
+ def handle_channel_msg_0xa0(self, is_flushed):
# Polyphonic key pressure / aftertouch: An kk vv
# n = channel, kk = polyphonic key pressure, vv = pressure value
- pass # TODO
+ c = self.cmd
+ if len(c) < 2:
+ self.check_for_garbage_flush(is_flushed)
+ return
+ self.es_block = self.es
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ note, pressure = c[0], c[1]
+ note_name = self.get_note_name(chan, note)
+ self.putx([0, ['Channel %d: %s of %d for note = %d \'%s\'' % \
+ (chan, status_bytes[msg][0], pressure, note, note_name),
+ 'ch %d: %s %d for note %d' % \
+ (chan, status_bytes[msg][1], pressure, note),
+ '%d: %s %d, N %d' % \
+ (chan, status_bytes[msg][2], pressure, note)]])
+ self.cmd, self.state = [], 'IDLE'
+ self.soft_clear_status_byte()
def handle_controller_0x44(self):
# Legato footswitch: Bn 44 vv
# n = channel, vv = value (<= 0x3f: normal, > 0x3f: legato)
- chan, vv = (self.cmd[0] & 0x0f) + 1, self.cmd[2]
- t = 'normal' if vv <= 0x3f else 'legato'
- self.putx([0, ['Channel %d: control function \'%s\' = %s' % \
- (chan, control_functions[0x44], t)]])
+ c = self.cmd
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ vv = c[1]
+ t = ('normal', 'no') if vv <= 0x3f else ('legato', 'yes')
+ self.putx([0, ['Channel %d: %s \'%s\' = %s' % \
+ (chan, status_bytes[msg][0],
+ control_functions[0x44][0], t[0]),
+ 'ch %d: %s \'%s\' = %s' % \
+ (chan, status_bytes[msg][1],
+ control_functions[0x44][1], t[0]),
+ '%d: %s \'%s\' = %s' % \
+ (chan, status_bytes[msg][2],
+ control_functions[0x44][2], t[1])]])
def handle_controller_0x54(self):
# Portamento control (PTC): Bn 54 kk
# n = channel, kk = source note for pitch reference
- chan, kk = (self.cmd[0] & 0x0f) + 1, self.cmd[2]
- self.putx([0, ['Channel %d: control function \'%s\' (source note ' \
- '= %d)' % (chan, control_functions[0x54], kk)]])
+ c = self.cmd
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ kk = c[1]
+ kk_name = self.get_note_name(chan, kk)
+ self.putx([0, ['Channel %d: %s \'%s\' (source note = %d / %s)' % \
+ (chan, status_bytes[msg][0],
+ control_functions[0x54][0], kk, kk_name),
+ 'ch %d: %s \'%s\' (source note = %d)' % \
+ (chan, status_bytes[msg][1],
+ control_functions[0x54][1], kk),
+ '%d: %s \'%s\' (src N %d)' % \
+ (chan, status_bytes[msg][2],
+ control_functions[0x54][2], kk)]])
def handle_controller_generic(self):
c = self.cmd
- chan, fn, param = (c[0] & 0x0f) + 1, c[1], c[2]
- ctrl_fn = control_functions.get(fn, 'undefined')
- self.putx([0, ['Channel %d: control change to function \'%s\' ' \
- '(param = 0x%02x)' % (chan, ctrl_fn, param)]])
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ fn, param = c[0], c[1]
+ default_name = 'undefined'
+ ctrl_fn = control_functions.get(fn, default_name)
+ if ctrl_fn == default_name:
+ ctrl_fn = ('undefined 0x%02x' % fn, 'undef 0x%02x' % fn, '0x%02x' % fn)
+ self.putx([0, ['Channel %d: %s \'%s\' (param = 0x%02x)' % \
+ (chan, status_bytes[msg][0], ctrl_fn[0], param),
+ 'ch %d: %s \'%s\' (param = 0x%02x)' % \
+ (chan, status_bytes[msg][1], ctrl_fn[1], param),
+ '%d: %s \'%s\' is 0x%02x' % \
+ (chan, status_bytes[msg][2], ctrl_fn[2], param)]])
- def handle_channel_msg_0xb0(self):
+ def handle_channel_mode(self):
+ # Channel Mode: Bn mm vv
+ # n = channel, mm = mode number (120 - 127), vv = value
+ c = self.cmd
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ mm, vv = c[0], c[1]
+ mode_fn = control_functions.get(mm, ('undefined', 'undef', 'undef'))
+ # Decode the value based on the mode number.
+ vv_string = ('', '')
+ if mm == 122: # mode = local control?
+ if vv == 0:
+ vv_string = ('off', 'off')
+ elif vv == 127: # mode = poly mode on?
+ vv_string = ('on', 'on')
+ else:
+ vv_string = ('(non-standard param value of 0x%02x)' % vv,
+ '0x%02x' % vv)
+ elif mm == 126: # mode = mono mode on?
+ if vv != 0:
+ vv_string = ('(%d channels)' % vv, '(%d ch)' % vv)
+ else:
+ vv_string = ('(channels \'basic\' through 16)',
+ '(ch \'basic\' thru 16)')
+ elif vv != 0: # All other channel mode messages expect vv == 0.
+ vv_string = ('(non-standard param value of 0x%02x)' % vv,
+ '0x%02x' % vv)
+ self.putx([0, ['Channel %d: %s \'%s\' %s' % \
+ (chan, status_bytes[msg][0], mode_fn[0], vv_string[0]),
+ 'ch %d: %s \'%s\' %s' % \
+ (chan, status_bytes[msg][1], mode_fn[1], vv_string[1]),
+ '%d: %s \'%s\' %s' % \
+ (chan, status_bytes[msg][2], mode_fn[2], vv_string[1])]])
+ self.cmd, self.state = [], 'IDLE'
+ self.soft_clear_status_byte()
+
+ def handle_channel_msg_0xb0(self, is_flushed):
# Control change (or channel mode messages): Bn cc vv
# n = channel, cc = control number (0 - 119), vv = control value
c = self.cmd
- if (len(c) >= 2) and (c[1] in range(0x78, 0x7f + 1)):
- # This is not a control change, but rather a channel mode message.
- # TODO: Handle channel mode messages.
- return
- if len(c) < 3:
+ if len(c) < 2:
+ self.check_for_garbage_flush(is_flushed)
return
self.es_block = self.es
- handle_ctrl = getattr(self, 'handle_controller_0x%02x' % c[1],
+ if c[0] in range(0x78, 0x7f + 1):
+ self.handle_channel_mode()
+ return
+ handle_ctrl = getattr(self, 'handle_controller_0x%02x' % c[0],
self.handle_controller_generic)
handle_ctrl()
self.cmd, self.state = [], 'IDLE'
+ self.soft_clear_status_byte()
- def handle_channel_msg_0xc0(self):
+ def handle_channel_msg_0xc0(self, is_flushed):
# Program change: Cn pp
# n = channel, pp = program number (0 - 127)
- pass # TODO
+ c = self.cmd
+ if len(c) < 1:
+ self.check_for_garbage_flush(is_flushed)
+ return
+ self.es_block = self.es
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ pp = self.cmd[0] + 1
+ change_type = 'instrument'
+ name = ''
+ if chan != 10: # channel != percussion
+ name = gm_instruments.get(pp, 'undefined')
+ else:
+ change_type = 'drum kit'
+ name = drum_kit.get(pp, 'undefined')
+ self.putx([0, ['Channel %d: %s to %s %d (assuming %s)' % \
+ (chan, status_bytes[msg][0], change_type, pp, name),
+ 'ch %d: %s to %s %d' % \
+ (chan, status_bytes[msg][1], change_type, pp),
+ '%d: %s %d' % \
+ (chan, status_bytes[msg][2], pp)]])
+ self.cmd, self.state = [], 'IDLE'
+ self.soft_clear_status_byte()
- def handle_channel_msg_0xd0(self):
+ def handle_channel_msg_0xd0(self, is_flushed):
# Channel pressure / aftertouch: Dn vv
# n = channel, vv = pressure value
- pass # TODO
+ c = self.cmd
+ if len(c) < 1:
+ self.check_for_garbage_flush(is_flushed)
+ return
+ self.es_block = self.es
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ vv = self.cmd[0]
+ self.putx([0, ['Channel %d: %s %d' % (chan, status_bytes[msg][0], vv),
+ 'ch %d: %s %d' % (chan, status_bytes[msg][1], vv),
+ '%d: %s %d' % (chan, status_bytes[msg][2], vv)]])
+ self.cmd, self.state = [], 'IDLE'
+ self.soft_clear_status_byte()
- def handle_channel_msg_0xe0(self):
+ def handle_channel_msg_0xe0(self, is_flushed):
# Pitch bend change: En ll mm
# n = channel, ll = pitch bend change LSB, mm = pitch bend change MSB
- pass # TODO
+ c = self.cmd
+ if len(c) < 2:
+ self.check_for_garbage_flush(is_flushed)
+ return
+ self.es_block = self.es
+ msg, chan = self.status_byte & 0xf0, (self.status_byte & 0x0f) + 1
+ ll, mm = self.cmd[0], self.cmd[1]
+ decimal = (mm << 7) + ll
+ self.putx([0, ['Channel %d: %s 0x%02x 0x%02x (%d)' % \
+ (chan, status_bytes[msg][0], ll, mm, decimal),
+ 'ch %d: %s 0x%02x 0x%02x (%d)' % \
+ (chan, status_bytes[msg][1], ll, mm, decimal),
+ '%d: %s (%d)' % \
+ (chan, status_bytes[msg][2], decimal)]])
+ self.cmd, self.state = [], 'IDLE'
+ self.soft_clear_status_byte()
- def handle_channel_msg_generic(self):
- msg_type = self.cmd[0] & 0xf0
- self.putx([0, ['Unknown channel message type: 0x%02x' % msg_type]])
- # TODO: Handle properly.
+ def handle_channel_msg_generic(self, is_flushed):
+ # TODO: It should not be possible to hit this code.
+ # It currently can not be unit tested.
+ msg_type = self.status_byte & 0xf0
+ self.es_block = self.es
+ self.putx([2, ['Unknown channel message type: 0x%02x' % msg_type]])
+ self.cmd, self.state = [], 'IDLE'
+ self.soft_clear_status_byte()
def handle_channel_msg(self, newbyte):
- self.cmd.append(newbyte)
- msg_type = self.cmd[0] & 0xf0
+ if newbyte is not None:
+ if newbyte >= 0x80:
+ self.set_status_byte(newbyte)
+ else:
+ self.cmd.append(newbyte)
+ msg_type = self.status_byte & 0xf0
handle_msg = getattr(self, 'handle_channel_msg_0x%02x' % msg_type,
self.handle_channel_msg_generic)
- handle_msg()
+ handle_msg(newbyte is None)
def handle_sysex_msg(self, newbyte):
- # SysEx message: 1 status byte, x data bytes, EOX byte
- self.cmd.append(newbyte)
- if newbyte != 0xf7: # EOX
+ # SysEx message: 1 status byte, 1-3 manuf. bytes, x data bytes, EOX byte
+ #
+ # SysEx messages are variable length, can be terminated by EOX or
+ # by any non-SysReal status byte, and it clears self.status_byte.
+ #
+ # Note: All System message codes don't utilize self.status_byte.
+ self.hard_clear_status_byte()
+ if newbyte != 0xf7 and newbyte is not None: # EOX
+ self.cmd.append(newbyte)
return
self.es_block = self.es
- # TODO: Get message ID, vendor ID, message contents, etc.
- self.putx([0, ['SysEx message']])
+ # Note: Unlike other methods, this code pops bytes out of self.cmd
+ # to isolate the data.
+ msg = self.cmd.pop(0)
+ if len(self.cmd) < 1:
+ self.putx([2, ['%s: truncated manufacturer code (<1 bytes)' % \
+ status_bytes[msg][0],
+ '%s: truncated manufacturer (<1 bytes)' % \
+ status_bytes[msg][1],
+ '%s: trunc. manu.' % status_bytes[msg][2]]])
+ self.cmd, self.state = [], 'IDLE'
+ return
+ # Extract the manufacturer name (or SysEx realtime or non-realtime).
+ m1 = self.cmd.pop(0)
+ manu = (m1,)
+ if m1 == 0x00: # If byte == 0, then 2 more manufacturer bytes follow.
+ if len(self.cmd) < 2:
+ self.putx([2, ['%s: truncated manufacturer code (<3 bytes)' % \
+ status_bytes[msg][0],
+ '%s: truncated manufacturer (<3 bytes)' % \
+ status_bytes[msg][1],
+ '%s: trunc. manu.' % status_bytes[msg][2]]])
+ self.cmd, self.state = [], 'IDLE'
+ return
+ manu = (m1, self.cmd.pop(0), self.cmd.pop(0))
+ default_name = 'undefined'
+ manu_name = sysex_manufacturer_ids.get(manu, default_name)
+ if manu_name == default_name:
+ if len(manu) == 3:
+ manu_name = ('%s (0x%02x 0x%02x 0x%02x)' % \
+ (default_name, manu[0], manu[1], manu[2]),
+ default_name)
+ else:
+ manu_name = ('%s (0x%02x)' % (default_name, manu[0]),
+ default_name)
+ else:
+ manu_name = (manu_name, manu_name)
+ # Extract the payload, display in 1 of 2 formats
+ # TODO: Write methods to decode SysEx realtime & non-realtime payloads.
+ payload0 = ''
+ payload1 = ''
+ while len(self.cmd) > 0:
+ byte = self.cmd.pop(0)
+ payload0 += '0x%02x ' % (byte)
+ payload1 += '%02x ' % (byte)
+ if payload0 == '':
+ payload0 = '<empty>'
+ payload1 = '<>'
+ payload = (payload0, payload1)
+ self.putx([0, ['%s: for \'%s\' with payload %s' % \
+ (status_bytes[msg][0], manu_name[0], payload[0]),
+ '%s: \'%s\', payload %s' % \
+ (status_bytes[msg][1], manu_name[1], payload[1]),
+ '%s: \'%s\', payload %s' % \
+ (status_bytes[msg][2], manu_name[1], payload[1])]])
+ self.cmd, self.state = [], 'IDLE'
+
+ def handle_syscommon_midi_time_code_quarter_frame_msg(self, newbyte):
+ # MIDI time code quarter frame: F1 nd
+ # n = message type
+ # d = values
+ #
+ # Note: All System message codes don't utilize self.status_byte,
+ # and System Exclusive and System Common clear it.
+ c = self.cmd
+ if len(c) < 2:
+ if newbyte is None:
+ self.handle_garbage_msg(None)
+ return
+ msg = c[0]
+ nn, dd = (c[1] & 0x70) >> 4, c[1] & 0x0f
+ group = ('System Common', 'SysCom', 'SC')
+ self.es_block = self.es
+ if nn != 7: # If message type does not contain SMPTE type.
+ self.putx([0, ['%s: %s of %s, value 0x%01x' % \
+ (group[0], status_bytes[msg][0],
+ quarter_frame_type[nn][0], dd),
+ '%s: %s of %s, value 0x%01x' % \
+ (group[1], status_bytes[msg][1],
+ quarter_frame_type[nn][1], dd),
+ '%s: %s of %s, value 0x%01x' % \
+ (group[2], status_bytes[msg][2],
+ quarter_frame_type[nn][1], dd)]])
+ self.cmd, self.state = [], 'IDLE'
+ return
+ tt = (dd & 0x6) >> 1
+ self.putx([0, ['%s: %s of %s, value 0x%01x for %s' % \
+ (group[0], status_bytes[msg][0], \
+ quarter_frame_type[nn][0], dd, smpte_type[tt]),
+ '%s: %s of %s, value 0x%01x for %s' % \
+ (group[1], status_bytes[msg][1], \
+ quarter_frame_type[nn][1], dd, smpte_type[tt]),
+ '%s: %s of %s, value 0x%01x for %s' % \
+ (group[2], status_bytes[msg][2], \
+ quarter_frame_type[nn][1], dd, smpte_type[tt])]])
self.cmd, self.state = [], 'IDLE'
def handle_syscommon_msg(self, newbyte):
- pass # TODO
+ # System common messages
+ #
+ # There are 5 simple formats (which are directly handled here) and
+ # 1 complex one called MIDI time code quarter frame.
+ #
+ # Note: While the MIDI lists 0xf7 as a "system common" message, it
+ # is actually only used with SysEx messages so it is processed there.
+ #
+ # Note: All System message codes don't utilize self.status_byte.
+ self.hard_clear_status_byte()
+ if newbyte is not None:
+ self.cmd.append(newbyte)
+ c = self.cmd
+ msg = c[0]
+ group = ('System Common', 'SysCom', 'SC')
+ if msg == 0xf1:
+ # MIDI time code quarter frame
+ self.handle_syscommon_midi_time_code_quarter_frame_msg(newbyte)
+ return
+ elif msg == 0xf2:
+ # Song position pointer: F2 ll mm
+ # ll = LSB position, mm = MSB position
+ if len(c) < 3:
+ if newbyte is None:
+ self.handle_garbage_msg(None)
+ return
+ ll, mm = c[1], c[2]
+ decimal = (mm << 7) + ll
+ self.es_block = self.es
+ self.putx([0, ['%s: %s 0x%02x 0x%02x (%d)' % \
+ (group[0], status_bytes[msg][0], ll, mm, decimal),
+ '%s: %s 0x%02x 0x%02x (%d)' % \
+ (group[1], status_bytes[msg][1], ll, mm, decimal),
+ '%s: %s (%d)' % \
+ (group[2], status_bytes[msg][2], decimal)]])
+ elif msg == 0xf3:
+ # Song select: F3 ss
+ # ss = song selection number
+ if len(c) < 2:
+ if newbyte is None:
+ self.handle_garbage_msg(None)
+ return
+ ss = c[1]
+ self.es_block = self.es
+ self.putx([0, ['%s: %s number %d' % \
+ (group[0], status_bytes[msg][0], ss),
+ '%s: %s number %d' % \
+ (group[1], status_bytes[msg][1], ss),
+ '%s: %s # %d' % \
+ (group[2], status_bytes[msg][2], ss)]])
+ elif msg == 0xf4 or msg == 0xf5 or msg == 0xf6:
+ # Undefined 0xf4, Undefined 0xf5, and Tune Request (respectively).
+ # All are only 1 byte long with no data bytes.
+ self.es_block = self.es
+ self.putx([0, ['%s: %s' % (group[0], status_bytes[msg][0]),
+ '%s: %s' % (group[1], status_bytes[msg][1]),
+ '%s: %s' % (group[2], status_bytes[msg][2])]])
+ self.cmd, self.state = [], 'IDLE'
def handle_sysrealtime_msg(self, newbyte):
# System realtime message: 0b11111ttt (t = message type)
- self.es_block = self.ss
- self.putx([0, ['System realtime message: %s' % status_bytes[newbyte]]])
+ #
+ # Important: These messages are handled differently from all others
+ # because they are allowed to temporarily interrupt other messages.
+ # The interrupted messages resume after the realtime message is done.
+ # Thus, they mostly leave 'self' the way it was found.
+ #
+ # Note: All System message codes don't utilize self.status_byte.
+ old_ss_block, old_es_block = self.ss_block, self.es_block
+ self.ss_block, self.es_block = self.ss, self.es
+ group = ('System Realtime', 'SysReal', 'SR')
+ self.putx([1, ['%s: %s' % (group[0], status_bytes[newbyte][0]),
+ '%s: %s' % (group[1], status_bytes[newbyte][1]),
+ '%s: %s' % (group[2], status_bytes[newbyte][2])]])
+ self.ss_block, self.es_block = old_ss_block, old_es_block
+ # Deliberately not resetting self.cmd or self.state.
+
+ def handle_garbage_msg(self, newbyte):
+ # Handle messages that are either not handled or are corrupt.
+ self.es_block = self.es
+ if newbyte is not None:
+ self.cmd.append(newbyte)
+ return
+ payload = '<empty>'
+ max_bytes = 16 # Put a limit on the length on the hex dump.
+ for index in range(len(self.cmd)):
+ if index == max_bytes:
+ payload += ' ...'
+ break
+ if index == 0:
+ payload = '0x%02x' % self.cmd[index]
+ else:
+ payload += ' 0x%02x' % self.cmd[index]
+ self.putx([2, ['UNHANDLED DATA: %s' % payload,
+ 'UNHANDLED', '???', '?']])
self.cmd, self.state = [], 'IDLE'
+ self.hard_clear_status_byte()
+
+ def handle_state(self, state, newbyte):
+ # 'newbyte' can either be:
+ # 1. Value between 0x00-0xff, deal with the byte normally.
+ # 2. Value of 'None' which means "flush any buffered data".
+ if state == 'HANDLE CHANNEL MSG':
+ self.handle_channel_msg(newbyte)
+ elif state == 'HANDLE SYSEX MSG':
+ self.handle_sysex_msg(newbyte)
+ elif state == 'HANDLE SYSCOMMON MSG':
+ self.handle_syscommon_msg(newbyte)
+ elif state == 'HANDLE SYSREALTIME MSG':
+ self.handle_sysrealtime_msg(newbyte)
+ elif state == 'BUFFER GARBAGE MSG':
+ self.handle_garbage_msg(newbyte)
+
+ def get_next_state(self, newbyte):
+ # 'newbyte' must be a valid byte between 0x00 and 0xff.
+ #
+ # Try to determine the state based off of the 'newbyte' parameter.
+ if newbyte in range(0x80, 0xef + 1):
+ return 'HANDLE CHANNEL MSG'
+ if newbyte == 0xf0:
+ return 'HANDLE SYSEX MSG'
+ if newbyte in range(0xf1, 0xf7):
+ return'HANDLE SYSCOMMON MSG'
+ if newbyte in range(0xf8, 0xff + 1):
+ return 'HANDLE SYSREALTIME MSG'
+ # Passing 0xf7 is an error; messages don't start with 0xf7.
+ if newbyte == 0xf7:
+ return 'BUFFER GARBAGE MSG'
+ # Next, base the state off of self.status_byte.
+ if self.status_byte < 0x80:
+ return 'BUFFER GARBAGE MSG'
+ return self.get_next_state(self.status_byte)
def decode(self, ss, es, data):
ptype, rxtx, pdata = data
+ state = 'IDLE'
# For now, ignore all UART packets except the actual data packets.
if ptype != 'DATA':
return
- self.ss, self.es = ss, es
+ # We're only interested in the byte value (not individual bits).
+ pdata = pdata[0]
# Short MIDI overview:
# - Status bytes are 0x80-0xff, data bytes are 0x00-0x7f.
# - Most messages: 1 status byte, 1-2 data bytes.
# - Real-time system messages: always 1 byte.
# - SysEx messages: 1 status byte, n data bytes, EOX byte.
+ #
+ # Aspects of the MIDI protocol that complicate decoding:
+ # - MIDI System Realtime messages can briefly interrupt other
+ # messages already in progress.
+ # - "Running Status" allows for omitting the status byte in most
+ # scenarios if sequential messages have the same status byte.
+ # - System Exclusive (SysEx) messages can be terminated by ANY
+ # status byte (not limited to EOX byte).
# State machine.
- if self.state == 'IDLE':
- # Wait until we see a status byte (bit 7 must be set).
- if pdata < 0x80:
- return # TODO: How to handle? Ignore?
+ if pdata >= 0x80 and pdata != 0xf7:
+ state = self.get_next_state(pdata)
+ if state != 'HANDLE SYSREALTIME MSG' and self.state != 'IDLE':
+ # Flush the previous data since a new message is starting.
+ self.handle_state(self.state, None)
+ # Cache ss and es -after- flushing previous data.
+ self.ss, self.es = ss, es
# This is a status byte, remember the start sample.
- self.ss_block = ss
- if pdata in range(0x80, 0xef + 1):
- self.state = 'HANDLE CHANNEL MSG'
- elif pdata == 0xf0:
- self.state = 'HANDLE SYSEX MSG'
- elif pdata in range(0xf1, 0xf7 + 1):
- self.state = 'HANDLE SYSCOMMON MSG'
- elif pdata in range(0xf8, 0xff + 1):
- self.state = 'HANDLE SYSREALTIME MSG'
-
- # Yes, this is intentionally _not_ an 'elif' here.
- if self.state == 'HANDLE CHANNEL MSG':
- self.handle_channel_msg(pdata)
- elif self.state == 'HANDLE SYSEX MSG':
- self.handle_sysex_msg(pdata)
- elif self.state == 'HANDLE SYSCOMMON MSG':
- self.handle_syscommon_msg(pdata)
- elif self.state == 'HANDLE SYSREALTIME MSG':
- self.handle_sysrealtime_msg(pdata)
+ if state != 'HANDLE SYSREALTIME MSG':
+ self.ss_block = ss
+ elif self.state == 'IDLE' or self.state == 'BUFFER GARBAGE MSG':
+ # Deal with "running status" or that we're buffering garbage.
+ self.ss, self.es = ss, es
+ if self.state == 'IDLE':
+ self.ss_block = ss
+ state = self.get_next_state(pdata)
else:
- raise Exception('Invalid state: %s' % self.state)
+ self.ss, self.es = ss, es
+ state = self.state
+ # Yes, this is intentionally _not_ an 'elif' here.
+ if state != 'HANDLE SYSREALTIME MSG':
+ self.state = state
+ if state == 'BUFFER GARBAGE MSG':
+ self.status_byte = 0
+ self.handle_state(state, pdata)
projects / libsigrokdecode.git / blobdiff