From 35f4798673194733358cd3db19a4d2baf70887fd Mon Sep 17 00:00:00 2001 From: cbdev Date: Fri, 15 Jan 2021 21:35:21 +0100 Subject: Implement EPN's for the rtpmidi backend --- backends/midi.c | 3 +- backends/rtpmidi.c | 177 ++++++++++++++++++++++++++++++++++++++++++++++------ backends/rtpmidi.h | 20 ++++-- backends/rtpmidi.md | 13 ++++ backends/winmidi.c | 2 +- 5 files changed, 191 insertions(+), 24 deletions(-) diff --git a/backends/midi.c b/backends/midi.c index 10c8c4a..4bf846a 100644 --- a/backends/midi.c +++ b/backends/midi.c @@ -247,6 +247,7 @@ static int midi_set(instance* inst, size_t num, channel** c, channel_value* v){ } break; case pitchbend: + //TODO check whether this actually works that well midi_tx(data->port, ident.fields.type, ident.fields.channel, ident.fields.control, (v[u].normalised * 16383.0) - 8192); break; default: @@ -282,7 +283,7 @@ static char* midi_type_name(uint8_t type){ return "unknown"; } -//this state machine is used more-or-less verbatim in the winmidi and jack backends - fixes need to be applied there, too +//this state machine is used more-or-less verbatim in the winmidi, rtpmidi and jack backends - fixes need to be applied there, too static void midi_handle_epn(instance* inst, uint8_t chan, uint16_t control, uint16_t value){ midi_instance_data* data = (midi_instance_data*) inst->impl; midi_channel_ident ident = { diff --git a/backends/rtpmidi.c b/backends/rtpmidi.c index 8d5525c..3a54e26 100644 --- a/backends/rtpmidi.c +++ b/backends/rtpmidi.c @@ -429,6 +429,10 @@ static char* rtpmidi_type_name(uint8_t type){ return "pitch"; case program: return "program"; + case rpn: + return "rpn"; + case nrpn: + return "nrpn"; } return "unknown"; } @@ -579,6 +583,13 @@ static int rtpmidi_configure_instance(instance* inst, char* option, char* value) LOGPF("Unknown instance mode %s for instance %s", value, inst->name); return 1; } + else if(!strcmp(option, "epn-tx")){ + data->epn_tx_short = 0; + if(!strcmp(value, "short")){ + data->epn_tx_short = 1; + } + return 0; + } else if(!strcmp(option, "ssrc")){ data->ssrc = strtoul(value, NULL, 0); if(!data->ssrc){ @@ -707,6 +718,14 @@ static channel* rtpmidi_channel(instance* inst, char* spec, uint8_t flags){ ident.fields.type = note; next_token += 4; } + else if(!strncmp(next_token, "rpn", 3)){ + ident.fields.type = rpn; + next_token += 3; + } + else if(!strncmp(next_token, "nrpn", 4)){ + ident.fields.type = nrpn; + next_token += 4; + } else if(!strncmp(next_token, "pressure", 8)){ ident.fields.type = pressure; next_token += 8; @@ -733,6 +752,32 @@ static channel* rtpmidi_channel(instance* inst, char* spec, uint8_t flags){ return NULL; } +static size_t rtpmidi_push_midi(uint8_t* payload, size_t bytes_left, uint8_t type, uint8_t channel, uint8_t control, uint16_t value){ + //FIXME this is a bit simplistic but it works for now + if(bytes_left < 4){ + return 0; + } + + //encode timestamp + payload[0] = 0; + + //encode midi command + payload[1] = type | channel; + payload[2] = control; + payload[3] = value & 0x7F; + + if(type == pitchbend){ + payload[2] = value & 0x7F; + payload[3] = (value >> 7) & 0x7F; + } + //channel-wides aftertouch and program are only 2 bytes + else if(type == aftertouch || type == program){ + payload[2] = payload[3]; + return 3; + } + return 4; +} + static int rtpmidi_set(instance* inst, size_t num, channel** c, channel_value* v){ rtpmidi_instance_data* data = (rtpmidi_instance_data*) inst->impl; uint8_t frame[RTPMIDI_PACKET_BUFFER] = ""; @@ -741,6 +786,7 @@ static int rtpmidi_set(instance* inst, size_t num, channel** c, channel_value* v size_t offset = sizeof(rtpmidi_header) + sizeof(rtpmidi_command_header), u = 0; uint8_t* payload = frame + offset; rtpmidi_channel_ident ident; + size_t command_length = 0; rtp_header->vpxcc = RTPMIDI_HEADER_MAGIC; //some receivers seem to have problems reading rfcs and interpreting the marker bit correctly @@ -757,27 +803,37 @@ static int rtpmidi_set(instance* inst, size_t num, channel** c, channel_value* v for(u = 0; u < num; u++){ ident.label = c[u]->ident; - //encode timestamp - payload[0] = 0; - - //encode midi command - payload[1] = ident.fields.type | ident.fields.channel; - payload[2] = ident.fields.control; - payload[3] = v[u].normalised * 127.0; - - if(ident.fields.type == pitchbend){ - payload[2] = ((int)(v[u].normalised * 16383.0)) & 0x7F; - payload[3] = (((int)(v[u].normalised * 16383.0)) >> 7) & 0x7F; + switch(ident.fields.type){ + case rpn: + case nrpn: + //transmit parameter number + command_length = rtpmidi_push_midi(payload + offset, sizeof(frame) - offset, cc, ident.fields.channel, (ident.fields.type == rpn) ? 101 : 99, (ident.fields.control >> 7) & 0x7F); + command_length += rtpmidi_push_midi(payload + offset + command_length, sizeof(frame) - offset, cc, ident.fields.channel, (ident.fields.type == rpn) ? 100 : 98, ident.fields.control & 0x7F); + + //transmit parameter value + command_length += rtpmidi_push_midi(payload + offset + command_length, sizeof(frame) - offset, cc, ident.fields.channel, 6, (((uint16_t) (v[u].normalised * 16383.0)) >> 7) & 0x7F); + command_length += rtpmidi_push_midi(payload + offset + command_length, sizeof(frame) - offset, cc, ident.fields.channel, 38, ((uint16_t) (v[u].normalised * 16383.0)) & 0x7F); + + if(!data->epn_tx_short){ + //clear active parameter + command_length += rtpmidi_push_midi(payload + offset + command_length, sizeof(frame) - offset, cc, ident.fields.channel, 101, 127); + command_length += rtpmidi_push_midi(payload + offset + command_length, sizeof(frame) - offset, cc, ident.fields.channel, 100, 127); + } + break; + case pitchbend: + //TODO check whether this works + command_length = rtpmidi_push_midi(payload + offset, sizeof(frame) - offset, ident.fields.type, ident.fields.channel, ident.fields.control, v[u].normalised * 16383.0); + break; + default: + command_length = rtpmidi_push_midi(payload + offset, sizeof(frame) - offset, ident.fields.type, ident.fields.channel, ident.fields.control, v[u].normalised * 127.0); } - //channel-wides aftertouch and program are only 2 bytes - else if(ident.fields.type == aftertouch || ident.fields.type == program){ - payload[2] = payload[3]; - payload -= 1; - offset -= 1; + + if(command_length == 0){ + LOGPF("Transmit buffer size exceeded on %s", inst->name); + break; } - payload += 4; - offset += 4; + offset += command_length; } //update command section length @@ -929,6 +985,79 @@ static int rtpmidi_handle_applemidi(instance* inst, int fd, uint8_t* frame, size return 0; } +//this state machine was copied more-or-less verbatim from the alsa midi implementation - fixes there will need to be integrated +static void rtpmidi_handle_epn(instance* inst, uint8_t chan, uint16_t control, uint16_t value){ + rtpmidi_instance_data* data = (rtpmidi_instance_data*) inst->impl; + rtpmidi_channel_ident ident = { + .label = 0 + }; + channel* changed = NULL; + channel_value val; + + //switching between nrpn and rpn clears all valid bits + if(((data->epn_status[chan] & EPN_NRPN) && (control == 101 || control == 100)) + || (!(data->epn_status[chan] & EPN_NRPN) && (control == 99 || control == 98))){ + data->epn_status[chan] &= ~(EPN_NRPN | EPN_PARAMETER_LO | EPN_PARAMETER_HI); + } + + //setting an address always invalidates the value valid bits + if(control >= 98 && control <= 101){ + data->epn_status[chan] &= ~EPN_VALUE_HI; + } + + //parameter hi + if(control == 101 || control == 99){ + data->epn_control[chan] &= 0x7F; + data->epn_control[chan] |= value << 7; + data->epn_status[chan] |= EPN_PARAMETER_HI | ((control == 99) ? EPN_NRPN : 0); + if(control == 101 && value == 127){ + data->epn_status[chan] &= ~EPN_PARAMETER_HI; + } + } + + //parameter lo + if(control == 100 || control == 98){ + data->epn_control[chan] &= ~0x7F; + data->epn_control[chan] |= value & 0x7F; + data->epn_status[chan] |= EPN_PARAMETER_LO | ((control == 98) ? EPN_NRPN : 0); + if(control == 100 && value == 127){ + data->epn_status[chan] &= ~EPN_PARAMETER_LO; + } + } + + //value hi, clears low, mark as update candidate + if(control == 6 + //check if parameter is set before accepting value update + && ((data->epn_status[chan] & (EPN_PARAMETER_HI | EPN_PARAMETER_LO)) == (EPN_PARAMETER_HI | EPN_PARAMETER_LO))){ + data->epn_value[chan] = value << 7; + data->epn_status[chan] |= EPN_VALUE_HI; + } + + //value lo, flush the value + if(control == 38 + && data->epn_status[chan] & EPN_VALUE_HI){ + data->epn_value[chan] &= ~0x7F; + data->epn_value[chan] |= value & 0x7F; + data->epn_status[chan] &= ~EPN_VALUE_HI; + + if(cfg.detect){ + LOGPF("Incoming EPN data on channel %s.ch%d.%s%d", inst->name, chan, data->epn_status[chan] & EPN_NRPN ? "nrpn" : "rpn", data->epn_control[chan]); + } + + //find the updated channel + ident.fields.type = data->epn_status[chan] & EPN_NRPN ? nrpn : rpn; + ident.fields.channel = chan; + ident.fields.control = data->epn_control[chan]; + val.normalised = (double) data->epn_value[chan] / 16383.0; + + //push the new value + changed = mm_channel(inst, ident.label, 0); + if(changed){ + mm_channel_event(changed, val); + } + } +} + static int rtpmidi_parse(instance* inst, uint8_t* frame, size_t bytes){ uint16_t length = 0; size_t offset = 1, decode_time = 0, command_bytes = 0; @@ -1004,6 +1133,7 @@ static int rtpmidi_parse(instance* inst, uint8_t* frame, size_t bytes){ if(ident.fields.type == aftertouch || ident.fields.type == program){ ident.fields.control = 0; val.normalised = (double) frame[offset] / 127.0; + val.raw.u64 = frame[offset]; offset++; } //two-byte command @@ -1016,16 +1146,19 @@ static int rtpmidi_parse(instance* inst, uint8_t* frame, size_t bytes){ if(ident.fields.type == pitchbend){ ident.fields.control = 0; val.normalised = (double)((frame[offset] << 7) | frame[offset - 1]) / 16383.0; + val.raw.u64 = (frame[offset] << 7) | frame[offset - 1]; } else{ ident.fields.control = frame[offset - 1]; val.normalised = (double) frame[offset] / 127.0; + val.raw.u64 = frame[offset]; } //fix-up note off events if(ident.fields.type == 0x80){ ident.fields.type = note; val.normalised = 0; + val.raw.u64 = 0; } offset++; @@ -1034,6 +1167,14 @@ static int rtpmidi_parse(instance* inst, uint8_t* frame, size_t bytes){ DBGPF("Decoded command type %02X channel %d control %d value %f", ident.fields.type, ident.fields.channel, ident.fields.control, val.normalised); + //forward EPN CCs to the EPN state machine + if(ident.fields.type == cc + && ((ident.fields.control <= 101 && ident.fields.control >= 98) + || ident.fields.control == 6 + || ident.fields.control == 38)){ + rtpmidi_handle_epn(inst, ident.fields.channel, ident.fields.control, val.raw.u64); + } + if(cfg.detect){ if(ident.fields.type == pitchbend || ident.fields.type == aftertouch diff --git a/backends/rtpmidi.h b/backends/rtpmidi.h index 5f1621e..e88530f 100644 --- a/backends/rtpmidi.h +++ b/backends/rtpmidi.h @@ -32,6 +32,11 @@ static int rtpmidi_shutdown(size_t n, instance** inst); #define DNS_OPCODE(a) (((a) & 0x78) >> 3) #define DNS_RESPONSE(a) ((a) & 0x80) +#define EPN_NRPN 8 +#define EPN_PARAMETER_HI 4 +#define EPN_PARAMETER_LO 2 +#define EPN_VALUE_HI 1 + enum /*_rtpmidi_channel_type*/ { none = 0, note = 0x90, @@ -39,7 +44,9 @@ enum /*_rtpmidi_channel_type*/ { cc = 0xB0, program = 0xC0, aftertouch = 0xD0, - pitchbend = 0xE0 + pitchbend = 0xE0, + rpn = 0xF1, + nrpn = 0xF2 }; typedef enum /*_rtpmidi_instance_mode*/ { @@ -50,10 +57,10 @@ typedef enum /*_rtpmidi_instance_mode*/ { typedef union { struct { - uint8_t pad[5]; + uint8_t pad[4]; uint8_t type; uint8_t channel; - uint8_t control; + uint16_t control; } fields; uint64_t label; } rtpmidi_channel_ident; @@ -68,7 +75,7 @@ typedef struct /*_rtpmidi_peer*/ { ssize_t invite; //invite-list index for apple-mode learned peers (used to track ipv6/ipv4 overlapping invitations) } rtpmidi_peer; -typedef struct /*_rtmidi_instance_data*/ { +typedef struct /*_rtpmidi_instance_data*/ { rtpmidi_instance_mode mode; int fd; @@ -80,6 +87,11 @@ typedef struct /*_rtmidi_instance_data*/ { uint32_t ssrc; uint16_t sequence; + uint8_t epn_tx_short; + uint16_t epn_control[16]; + uint16_t epn_value[16]; + uint8_t epn_status[16]; + //apple-midi config char* accept; uint64_t last_announce; diff --git a/backends/rtpmidi.md b/backends/rtpmidi.md index 9f56f3d..8014572 100644 --- a/backends/rtpmidi.md +++ b/backends/rtpmidi.md @@ -38,6 +38,7 @@ Common instance configuration parameters | `ssrc` | `0xDEADBEEF` | Randomly generated | 32-bit synchronization source identifier | | `mode` | `direct` | none | Instance session management mode (`direct` or `apple`) | | `peer` | `10.1.2.3 9001` | none | MIDI session peer, may be specified multiple times. Bypasses session discovery (but still performs session negotiation) | +| `epn-tx` | `short` | `full` | Configure whether to clear the active parameter number after transmitting an `nrpn` or `rpn` parameter. | `direct` mode instance configuration parameters @@ -64,6 +65,8 @@ The `rtpmidi` backend supports mapping different MIDI events to MIDIMonster chan * `aftertouch` - Channel-wide aftertouch messages * `pitch` - Channel pitchbend messages * `program` - Channel program change messages +* `rpn` - Registered parameter numbers (14-bit extension) +* `nrpn` - Non-registered parameter numbers (14-bit extension) A MIDIMonster channel is specified using the syntax `channel.`. The shorthand `ch` may be used instead of the word `channel` (Note that `channel` here refers to the MIDI channel number). @@ -74,6 +77,9 @@ MIDI channels range from `0` to `15`. Each MIDI channel consists of 128 notes (n additionally each have a pressure control, 128 CC's (numbered likewise), a channel pressure control (also called 'channel aftertouch') and a pitch control which may all be mapped to individual MIDIMonster channels. +Every MIDI channel also provides `rpn` and `nrpn` controls, which are implemented on top of the MIDI protocol, using +the CC controls 101/100/99/98/38/6. Both control types have 14-bit IDs and 14-bit values. + Example mappings: ``` @@ -82,6 +88,7 @@ rmidi1.channel15.pressure1 > rmidi1.channel0.note0 rmidi1.ch1.aftertouch > rmidi2.ch2.cc0 rmidi1.ch0.pitch > rmidi2.ch1.pitch rmidi2.ch15.note1 > rmidi2.ch2.program +rmidi2.ch0.nrpn900 > rmidi1.ch1.rpn1 ``` #### Known bugs / problems @@ -93,6 +100,12 @@ The mDNS and DNS-SD implementations in this backend are extremely terse, to the specifications in multiple cases. Due to the complexity involved in supporting these protocols, problems arising from this will be considered a bug only in cases where they hinder normal operation of the backend. +Extended parameter numbers (EPNs, the `rpn` and `nrpn` control types) will also generate events on the controls (CC 101 through +98, 38 and 6) that are used as the lower layer transport. When using EPNs, mapping those controls is probably not useful. + +EPN control types support only the full 14-bit transfer encoding, not the shorter variant transmitting only the 7 +high-order bits. This may be changed if there is sufficient interest in the functionality. + mDNS discovery may announce flawed records when run on a host with multiple active interfaces. While this backend should be reasonably stable, there may be problematic edge cases simply due to the diff --git a/backends/winmidi.c b/backends/winmidi.c index a1fa686..649af2e 100644 --- a/backends/winmidi.c +++ b/backends/winmidi.c @@ -200,7 +200,7 @@ static void winmidi_tx(HMIDIOUT port, uint8_t type, uint8_t channel, uint8_t con output.components.status = type | channel; output.components.data1 = control; - output.components.data2 = value; + output.components.data2 = value & 0x7F; if(type == pitchbend){ output.components.data1 = value & 0x7F; -- cgit v1.2.3