Implement LOAD_SECONDARY_CONTROL

pycoax/coax/__init__.py

@@ -8,6 +8,7 @@ from .protocol import (
     PowerOnResetCompletePollResponse,
     KeystrokePollResponse,
     Control,
+    SecondaryControl,
     poll,
     poll_ack,
     read_status,

pycoax/coax/protocol.py

@@ -152,6 +152,19 @@ class Control:
                 f'cursor_reverse={self.cursor_reverse}, '
                 f'cursor_blink={self.cursor_blink}>')
 
+class SecondaryControl:
+    """Terminal secondary control register."""
+
+    def __init__(self, big=False):
+        self.big = big
+
+    @property
+    def value(self):
+        return bool(self.big) | 0
+
+    def __repr__(self):
+        return f'<SecondaryControl big={self.big}>'
+
 def poll(interface, action=PollAction.NONE, **kwargs):
     """Execute a POLL command."""
     command_word = (action.value << 8) | _pack_command_word(Command.POLL)
@@ -233,9 +246,11 @@ def load_control_register(interface, control, **kwargs):
 
     _execute_write_command(interface, command_word, bytes([control.value]), **kwargs)
 
-def load_secondary_control(interface):
+def load_secondary_control(interface, control, **kwargs):
     """Execute a LOAD_SECONDARY_CONTROL command."""
-    raise NotImplementedError
+    command_word = _pack_command_word(Command.LOAD_SECONDARY_CONTROL)
+
+    _execute_write_command(interface, command_word, bytes([control.value]), **kwargs)
 
 def load_mask(interface):
     """Execute a LOAD_MASK command."""

pycoax/tests/test_protocol.py

@@ -4,7 +4,7 @@ from unittest.mock import Mock
 import context
 
 from coax import PollResponse, KeystrokePollResponse, ProtocolError
-from coax.protocol import Command, Status, TerminalId, Control, _execute_read_command, _execute_write_command, _pack_command_word, _unpack_command_word, _unpack_data_words, _unpack_data_word
+from coax.protocol import Command, Status, TerminalId, Control, SecondaryControl, _execute_read_command, _execute_write_command, _pack_command_word, _unpack_command_word, _unpack_data_words, _unpack_data_word
 
 class PollResponseTestCase(unittest.TestCase):
     def test_is_power_on_reset_complete(self):
@@ -89,6 +89,12 @@ class ControlTestCase(unittest.TestCase):
 
         self.assertEqual(control.value, 0b00000001)
 
+class SecondaryControlTestCase(unittest.TestCase):
+    def test_big(self):
+        control = SecondaryControl(big=True)
+
+        self.assertEqual(control.value, 0b00000001)
+
 class ExecuteReadCommandTestCase(unittest.TestCase):
     def setUp(self):
         self.interface = Mock()