2016-07-20 08:59:39 +08:00

212 lines
7.7 KiB
Python
Executable File

##
## This file is part of the libsigrokdecode project.
##
## Copyright (C) 2013 Uwe Hermann <uwe@hermann-uwe.de>
##
## 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
## the Free Software Foundation; either version 2 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
## 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
##
import sigrokdecode as srd
from .lists import *
RX = 0
TX = 1
class Decoder(srd.Decoder):
api_version = 2
id = 'midi'
name = 'MIDI'
longname = 'Musical Instrument Digital Interface'
desc = 'Musical Instrument Digital Interface (MIDI) protocol.'
license = 'gplv2+'
inputs = ['uart']
outputs = ['midi']
annotations = (
('text-verbose', 'Human-readable text (verbose)'),
)
def __init__(self):
self.cmd = []
self.state = 'IDLE'
self.ss = None
self.es = None
self.ss_block = None
self.es_block = None
def start(self):
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):
# Note off: 8n kk vv
# n = channel, kk = note, vv = velocity
c = self.cmd
if len(c) < 3:
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)]])
self.cmd, self.state = [], 'IDLE'
def handle_channel_msg_0x90(self):
# 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:
return
self.es_block = self.es
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.cmd, self.state = [], 'IDLE'
def handle_channel_msg_0xa0(self):
# Polyphonic key pressure / aftertouch: An kk vv
# n = channel, kk = polyphonic key pressure, vv = pressure value
pass # TODO
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)]])
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)]])
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)]])
def handle_channel_msg_0xb0(self):
# 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:
return
self.es_block = self.es
handle_ctrl = getattr(self, 'handle_controller_0x%02x' % c[1],
self.handle_controller_generic)
handle_ctrl()
self.cmd, self.state = [], 'IDLE'
def handle_channel_msg_0xc0(self):
# Program change: Cn pp
# n = channel, pp = program number (0 - 127)
pass # TODO
def handle_channel_msg_0xd0(self):
# Channel pressure / aftertouch: Dn vv
# n = channel, vv = pressure value
pass # TODO
def handle_channel_msg_0xe0(self):
# Pitch bend change: En ll mm
# n = channel, ll = pitch bend change LSB, mm = pitch bend change MSB
pass # TODO
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(self, newbyte):
self.cmd.append(newbyte)
msg_type = self.cmd[0] & 0xf0
handle_msg = getattr(self, 'handle_channel_msg_0x%02x' % msg_type,
self.handle_channel_msg_generic)
handle_msg()
def handle_sysex_msg(self, newbyte):
# SysEx message: 1 status byte, x data bytes, EOX byte
self.cmd.append(newbyte)
if newbyte != 0xf7: # EOX
return
self.es_block = self.es
# TODO: Get message ID, vendor ID, message contents, etc.
self.putx([0, ['SysEx message']])
self.cmd, self.state = [], 'IDLE'
def handle_syscommon_msg(self, newbyte):
pass # TODO
def handle_sysrealtime_msg(self, newbyte):
# System realtime message: 0b11111ttt (t = message type)
self.es_block = self.es
self.putx([0, ['System realtime message: %s' % status_bytes[newbyte]]])
self.cmd, self.state = [], 'IDLE'
def decode(self, ss, es, data):
ptype, rxtx, pdata = data
# 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.
# 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?
# 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)