Merge pull request #396 from shuchitak/midi_ct_pause

Use CT_END tokens in MIDI to terminate connection

CHANGELOG.rst

@@ -17,6 +17,7 @@ UNRELEASED
   * FIXED:     Samples transferred to ADAT tx too frequently in TDM mode
   * FIXED:     S/MUX not initialised to a value based on DEFAULT_FREQ in clockgen
   * FIXED:     Trap when moving to DSD mode on XS3A based devices
+  * ADDED:     CT_END token based handshake in MIDI channels transactions
 
 4.0.0
 -----

lib_xua/api/xua_midi.h

@@ -1,4 +1,4 @@
-// Copyright 2011-2022 XMOS LIMITED.
+// Copyright 2011-2024 XMOS LIMITED.
 // This Software is subject to the terms of the XMOS Public Licence: Version 1.
 #ifndef _XUA_MIDI_H_
 #define _XUA_MIDI_H_
@@ -57,24 +57,25 @@ void midi_get_ack_or_data(chanend c, int &is_ack, unsigned int &datum);
 INLINE void midi_get_ack_or_data(chanend c, int &is_ack, unsigned int &datum) {
   if (testct(c)) {
     is_ack = 1;
-    (void) inct(c); // read 1-bytes control token
+    chkct(c, XS1_CT_END);
-    (void) inuchar(c);
-    (void) inuchar(c);
-    (void) inuchar(c);
   }
   else {
     is_ack = 0;
     datum = inuint(c);
+    chkct(c, XS1_CT_END);
   }
 }
 #endif
 
 INLINE void midi_send_ack(chanend c) {
-  outct(c, MIDI_ACK);
+  outct(c, XS1_CT_END);
-  outuchar(c, 0);
-  outuchar(c, 0);
-  outuchar(c, 0);
 }
+
+INLINE void midi_send_data(chanend c, unsigned int datum) {
+  outuint(c, datum);
+  outct(c, XS1_CT_END);
+}
+
 #define MIDI_RATE           (31250)
 #define MIDI_BITTIME        (XS1_TIMER_MHZ * 1000000 / MIDI_RATE)
 #define MIDI_BITTIME_2      (MIDI_BITTIME>>1)

lib_xua/src/core/buffer/ep/ep_buffer.xc

@@ -839,7 +839,7 @@ void XUA_Buffer_Ep(register chanend c_aud_out,
                     if (midi_data_remaining_to_device)
                     {
                         read_via_xc_ptr(datum, midi_from_host_rdptr);
-                        outuint(c_midi, datum);
+                        midi_send_data(c_midi, datum);
                         midi_from_host_rdptr += 4;
                         midi_data_remaining_to_device -= 4;
                     }
@@ -992,7 +992,7 @@ void XUA_Buffer_Ep(register chanend c_aud_out,
                     {
                         /* Read another word from the fifo and output it to MIDI thread */
                         read_via_xc_ptr(datum, midi_from_host_rdptr);
-                        outuint(c_midi, datum);
+                        midi_send_data(c_midi, datum);
                         midi_from_host_rdptr += 4;
                         midi_data_remaining_to_device -= 4;
                     }

lib_xua/src/midi/usb_midi.xc

@@ -197,7 +197,7 @@ void usb_midi(
                                 {
                                     // send data
                                     // printstr("uart->decouple: ");
-                                    outuint(c_midi, event);
+                                    midi_send_data(c_midi, event);
                                     waiting_for_ack = 1;
                                     th_count++;
                                 }
@@ -272,7 +272,7 @@ void usb_midi(
                 // have we got more data to send
                 if (!queue_is_empty(midi_to_host_fifo))
                 {
-                    outuint(c_midi, queue_pop_word(midi_to_host_fifo, midi_to_host_fifo_arr));
+                    midi_send_data(c_midi, queue_pop_word(midi_to_host_fifo, midi_to_host_fifo_arr));
                     th_count++;
                 }
                 else
@@ -296,7 +296,7 @@ void usb_midi(
                     {
                         // send data
                         event = byterev(event);
-                        outuint(c_midi, event);
+                        midi_send_data(c_midi, event);
                         th_count++;
                         waiting_for_ack = 1;
                     }

tests/test_midi/src/app_midi_simple.xc

@@ -148,7 +148,7 @@ void test(chanend c_midi){
                 unsigned midi[] = {commands[tx_cmd_count][0], commands[tx_cmd_count][1], commands[tx_cmd_count][2]};
                 // Even though this is a Tx to MIDI we use midi_in_parse_helper to form the packet from bytes
                 unsigned tx_packet = midi_in_parse_helper(midi, m_state);
-                outuint(c_midi, byterev(tx_packet));
+                midi_send_data(c_midi, byterev(tx_packet));
                 dprintf("Sent packet to midi: %u %u %u (0x%8x)\n", commands[tx_cmd_count][0], commands[tx_cmd_count][1], commands[tx_cmd_count][2], tx_packet);
                 t_tx += tx_interval;
                 tx_end += max_tx_time;