Support set_output_callback().

z80/_z80module.cpp

@@ -112,6 +112,23 @@ class machine : public B {
         return old_callback;
     }
 
+    void on_output(fast_u16 addr, fast_u8 value) {
+        if(!on_input_callback)
+            return;
+
+        PyObject *args = Py_BuildValue("(i, i)", addr, value);
+        decref_guard arg_guard(args);
+
+        PyObject *result = PyObject_CallObject(on_output_callback, args);
+        decref_guard result_guard(result);
+    }
+
+    PyObject *set_output_callback(PyObject *callback) {
+        PyObject *old_callback = on_output_callback;
+        on_output_callback = callback;
+        return old_callback;
+    }
+
     fast_u8 on_get_b() const { return state.b; }
     void on_set_b(fast_u8 n) { state.b = n; }
 
@@ -208,6 +225,7 @@ class machine : public B {
 
 private:
     PyObject *on_input_callback = nullptr;
+    PyObject *on_output_callback = nullptr;
 };
 
 static const unsigned max_instr_size = 4;

z80/machine.inc

@@ -214,6 +214,23 @@ static PyObject *set_input_callback(PyObject *self, PyObject *args) {
     Py_RETURN_NONE;
 }
 
+static PyObject *set_output_callback(PyObject *self, PyObject *args) {
+    PyObject *new_callback;
+    if(!PyArg_ParseTuple(args, "O:set_callback", &new_callback))
+        return nullptr;
+
+    if(!PyCallable_Check(new_callback)) {
+        PyErr_SetString(PyExc_TypeError, "parameter must be callable");
+        return nullptr;
+    }
+
+    auto &machine = cast_machine(self);
+    PyObject *old_callback = machine.set_output_callback(new_callback);
+    Py_XINCREF(new_callback);
+    Py_XDECREF(old_callback);
+    Py_RETURN_NONE;
+}
+
 static PyObject *run(PyObject *self, PyObject *args) {
     auto &machine = cast_machine(self);
     z80::events_mask::type events = machine.on_run();
@@ -266,6 +283,8 @@ static PyMethodDef methods[] = {
      "processing on reading, writing or executing them."},
     {"set_input_callback", set_input_callback, METH_VARARGS,
      "Set a callback function handling reading from ports."},
+    {"set_output_callback", set_output_callback, METH_VARARGS,
+     "Set a callback function handling writing to ports."},
     {"run", run, METH_NOARGS,
      "Run emulator until one or several events are signaled."},
 #if defined(Z80_MACHINE)