diff --git a/z80.h b/z80.h
index 341b690..66c8393 100644
--- a/z80.h
+++ b/z80.h
@@ -225,6 +225,7 @@ class root {
     unsigned on_get_int_mode() const { return 0; }
     void on_set_int_mode(unsigned mode) { unused(mode); }
     void on_set_is_int_disabled(bool f) { unused(f); }
+    fast_u8 on_get_int_vector() { return 0xFF; }
 
     void set_i_on_ld(fast_u8 i) { self().on_set_i(i); }
 
@@ -3771,7 +3772,7 @@ class internals::executor_base : public B {
                 break;
             case 2: {
                 // ack(7) w(3) w(3) r(3) r(3)
-                fast_u16 vector_addr = make16(self().on_get_i(), 0xff);
+                fast_u16 vector_addr = make16(self().on_get_i(), self().on_get_int_vector());
                 fast_u8 lo = self().on_read_cycle(vector_addr);
                 fast_u8 hi = self().on_read_cycle(inc16(vector_addr));
                 isr_addr = make16(hi, lo); }
diff --git a/z80/_z80module.cpp b/z80/_z80module.cpp
index edcede2..776cc24 100644
--- a/z80/_z80module.cpp
+++ b/z80/_z80module.cpp
@@ -72,13 +72,58 @@ class machine : public B {
     }
 
     fast_u8 on_read(fast_u16 addr) {
+        const fast_u8 default_value = 0xff;
         assert(addr < z80::address_space_size);
-        return state.memory[addr];
+
+        if(!on_read_callback) {
+            return state.memory[addr];
+        }
+
+        PyObject *arg = Py_BuildValue("(i)", addr);
+        decref_guard arg_guard(arg);
+
+        PyObject *result = PyObject_CallObject(on_read_callback, arg);
+        decref_guard result_guard(result);
+
+        if(!result) {
+            assert(0);  // TODO: stop();
+            return default_value;
+        }
+
+        if(!PyLong_Check(result)) {
+            PyErr_SetString(PyExc_TypeError, "returning value must be integer");
+            assert(0);  // TODO: stop();
+            return default_value;
+        }
+
+        return z80::mask8(PyLong_AsUnsignedLong(result));
+    }
+
+    PyObject *set_read_callback(PyObject *callback) {
+        PyObject *old_callback = on_read_callback;
+        on_read_callback = callback;
+        return old_callback;
     }
 
     void on_write(fast_u16 addr, fast_u8 n) {
         assert(addr < z80::address_space_size);
-        state.memory[addr] = n;
+
+        if(!on_write_callback) {
+            state.memory[addr] = n;
+            return;
+        }
+
+        PyObject *args = Py_BuildValue("(i, i)", addr, n);
+        decref_guard arg_guard(args);
+
+        PyObject *result = PyObject_CallObject(on_write_callback, args);
+        decref_guard result_guard(result);
+    }
+
+    PyObject *set_write_callback(PyObject *callback) {
+        PyObject *old_callback = on_write_callback;
+        on_write_callback = callback;
+        return old_callback;
     }
 
     fast_u8 on_input(fast_u16 addr) {
@@ -129,6 +174,49 @@ class machine : public B {
         return old_callback;
     }
 
+    void on_reti() {
+        base::on_reti();
+
+        if(on_reti_callback) {
+            PyObject *result = PyObject_CallObject(on_reti_callback, NULL);
+            decref_guard result_guard(result);
+        }
+    }
+
+    PyObject *set_reti_callback(PyObject *callback) {
+        PyObject *old_callback = on_reti_callback;
+        on_reti_callback = callback;
+        return old_callback;
+    }
+
+    fast_u8 on_get_int_vector() {
+        const fast_u8 default_value = 0xff;
+        if(!on_get_int_vector_callback)
+            return base::on_get_int_vector();
+
+        PyObject *result = PyObject_CallObject(on_get_int_vector_callback, NULL);
+        decref_guard result_guard(result);
+
+        if(!result) {
+            assert(0);  // TODO: stop();
+            return default_value;
+        }
+
+        if(!PyLong_Check(result)) {
+            PyErr_SetString(PyExc_TypeError, "returning value must be integer");
+            assert(0);  // TODO: stop();
+            return default_value;
+        }
+
+        return z80::mask8(PyLong_AsUnsignedLong(result));
+    }
+
+    PyObject *set_get_int_vector_callback(PyObject *callback) {
+        PyObject *old_callback = on_get_int_vector_callback;
+        on_get_int_vector_callback = callback;
+        return old_callback;
+    }
+
     fast_u8 on_get_b() const { return state.b; }
     void on_set_b(fast_u8 n) { state.b = n; }
 
@@ -224,8 +312,12 @@ class machine : public B {
     machine_state state;
 
 private:
+    PyObject *on_read_callback = nullptr;
+    PyObject *on_write_callback = nullptr;
     PyObject *on_input_callback = nullptr;
     PyObject *on_output_callback = nullptr;
+    PyObject *on_reti_callback = nullptr;
+    PyObject *on_get_int_vector_callback = nullptr;
 };
 
 static const unsigned max_instr_size = 4;
diff --git a/z80/machine.inc b/z80/machine.inc
index 00bb9b8..171ac00 100644
--- a/z80/machine.inc
+++ b/z80/machine.inc
@@ -197,6 +197,40 @@ static PyObject *unmark_addrs(PyObject *self, PyObject *args) {
     Py_RETURN_NONE;
 }
 
+static PyObject *set_read_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_read_callback(new_callback);
+    Py_XINCREF(new_callback);
+    Py_XDECREF(old_callback);
+    Py_RETURN_NONE;
+}
+
+static PyObject *set_write_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_write_callback(new_callback);
+    Py_XINCREF(new_callback);
+    Py_XDECREF(old_callback);
+    Py_RETURN_NONE;
+}
+
 static PyObject *set_input_callback(PyObject *self, PyObject *args) {
     PyObject *new_callback;
     if(!PyArg_ParseTuple(args, "O:set_callback", &new_callback))
@@ -231,6 +265,40 @@ static PyObject *set_output_callback(PyObject *self, PyObject *args) {
     Py_RETURN_NONE;
 }
 
+static PyObject *set_reti_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_reti_callback(new_callback);
+    Py_XINCREF(new_callback);
+    Py_XDECREF(old_callback);
+    Py_RETURN_NONE;
+}
+
+static PyObject *set_get_int_vector_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_get_int_vector_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();
@@ -281,10 +349,18 @@ static PyMethodDef methods[] = {
     {"unmark_addrs", unmark_addrs, METH_VARARGS,
      "Clear the marking on a range of memory bytes that indicates it requires custom "
      "processing on reading, writing or executing them."},
+    {"set_read_callback", set_read_callback, METH_VARARGS,
+     "Set a callback function handling reading from memory."},
+    {"set_write_callback", set_write_callback, METH_VARARGS,
+     "Set a callback function handling writing to memory."},
     {"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."},
+    {"set_reti_callback", set_reti_callback, METH_VARARGS,
+     "Set a callback function handling the reti instruction."},
+    {"set_get_int_vector_callback", set_get_int_vector_callback, METH_VARARGS,
+     "Set a callback function handling the interrupt mode 2 vector address."},
     {"run", run, METH_NOARGS,
      "Run emulator until one or several events are signaled."},
 #if defined(Z80_MACHINE)