Merge pull request #158 from rwaldron/152

Interrupts: deliver the state of the pin for change events. Closes gh-152
tessel · Apr 2, 2016 · c04a41c · c04a41c
2 parents 1c7c86e + fe05842
commit c04a41c
Show file tree

Hide file tree

Showing 3 changed files with 78 additions and 5 deletions.
diff --git a/firmware/port.c b/firmware/port.c
@@ -734,7 +734,16 @@ void port_handle_extint(PortData *p, u32 flags) {
             if (port_pin_supports_interrupt(p, pin)) {
                 Pin sys_pin = p->port->gpio[pin];
                 if (flags & (1 << pin_extint(sys_pin))) {
-                    port_send_status(p, REPLY_ASYNC_PIN_CHANGE_N + pin);
+                    u8 response = REPLY_ASYNC_PIN_CHANGE_N + pin;
+
+                    // If the pin's state is high, set bit 3
+                    // of the response byte. This will be used to
+                    // inform "change" listeners of the present state
+                    // at the moment of the interrupt.
+                    if (pin_read(port_selected_pin(p))) {
+                        response |= 1 << 3;
+                    }
+                    port_send_status(p, response);
                     if (eic_read_config(sys_pin) & EIC_CONFIG_SENSE_LEVEL) {
                         // Async level interrupts only trigger once
                         eic_config(sys_pin, EIC_CONFIG_SENSE_NONE);

diff --git a/node/tessel-export.js b/node/tessel-export.js
@@ -235,9 +235,9 @@ Tessel.Port = function(name, socketPath, board) {
         // This is some other async transaction
       } else if (byte >= REPLY.MIN_ASYNC) {
         // If this is a pin change
-        if (byte >= REPLY.ASYNC_PIN_CHANGE_N && byte < REPLY.ASYNC_PIN_CHANGE_N + 8) {
-          // Pull out which pin it is
-          var pin = this.pin[byte - REPLY.ASYNC_PIN_CHANGE_N];
+        if (byte >= REPLY.ASYNC_PIN_CHANGE_N && byte < REPLY.ASYNC_PIN_CHANGE_N + 16) {
+          // Pull out the pin number (requires clearing the value bit)
+          var pin = this.pin[(byte - REPLY.ASYNC_PIN_CHANGE_N) & ~(1 << 3)];
           // Get the mode change
           var mode = pin.interruptMode;
 
@@ -250,7 +250,13 @@ Tessel.Port = function(name, socketPath, board) {
           }
 
           // Emit the change
-          pin.emit(mode);
+          if (mode === 'change') {
+            // "change" is otherwise ambiguous.
+            pin.emit('change', (byte >> 3) & 1);
+          } else {
+            // high, low, rise & fall are _not_ ambiguous
+            pin.emit(mode);
+          }
         } else {
           // Some other async event
           this.emit('async-event', byte);

diff --git a/node/test/unit/tessel.js b/node/test/unit/tessel.js
@@ -1262,6 +1262,64 @@ exports['Tessel.Pin'] = {
     test.done();
   },
 
+  interruptChangeStateLow: function(test) {
+    test.expect(17);
+
+    var spy = sandbox.spy();
+
+    [2, 5, 6, 7].forEach(function(pinIndex) {
+      this.a.pin[pinIndex].on('change', spy);
+      this.b.pin[pinIndex].on('change', spy);
+
+      test.equal(this.a.pin[pinIndex].interruptMode, 'change');
+      test.equal(this.b.pin[pinIndex].interruptMode, 'change');
+
+      // Simulate receipt of pin state changes
+      this.a.sock.read.returns(new Buffer([REPLY.ASYNC_PIN_CHANGE_N + pinIndex]));
+      this.a.sock.emit('readable');
+
+      this.b.sock.read.returns(new Buffer([REPLY.ASYNC_PIN_CHANGE_N + pinIndex]));
+      this.b.sock.emit('readable');
+    }, this);
+
+    test.equal(spy.callCount, 8);
+
+    for (var i = 0; i < 8; i++) {
+      test.equal(spy.getCall(i).args[0], 0);
+    }
+
+    test.done();
+  },
+
+  interruptChangeStateHigh: function(test) {
+    test.expect(17);
+
+    var spy = sandbox.spy();
+
+    [2, 5, 6, 7].forEach(function(pinIndex) {
+      this.a.pin[pinIndex].on('change', spy);
+      this.b.pin[pinIndex].on('change', spy);
+
+      test.equal(this.a.pin[pinIndex].interruptMode, 'change');
+      test.equal(this.b.pin[pinIndex].interruptMode, 'change');
+
+      // Simulate receipt of pin state changes
+      this.a.sock.read.returns(new Buffer([(REPLY.ASYNC_PIN_CHANGE_N + pinIndex) | (1 << 3)]));
+      this.a.sock.emit('readable');
+
+      this.b.sock.read.returns(new Buffer([(REPLY.ASYNC_PIN_CHANGE_N + pinIndex) | (1 << 3)]));
+      this.b.sock.emit('readable');
+    }, this);
+
+    test.equal(spy.callCount, 8);
+
+    for (var i = 0; i < 8; i++) {
+      test.equal(spy.getCall(i).args[0], 1);
+    }
+
+    test.done();
+  },
+
   removeListener: function(test) {
     test.expect(14);