IBM 3179 EAB support

Author: lowobservable

README.md

@@ -33,6 +33,7 @@ emulation.
 
 Only CUT (Control Unit Terminal) type terminals are supported. I have tested oec with the following terminals:
 
+  * IBM 3179
   * IBM 3278-2
   * IBM 3472
   * IBM 3483-V (InfoWindow II)

oec/__main__.py

@@ -2,13 +2,13 @@
 import os
 import signal
 import logging
-from coax import open_serial_interface, TerminalType
+from coax import open_serial_interface, TerminalType, Feature
 
 from .args import parse_args
 from .interface import InterfaceWrapper
 from .controller import Controller
-from .device import get_ids, get_features, get_keyboard_description, UnsupportedDeviceError
-from .terminal import Terminal
+from .device import get_ids, get_features, UnsupportedDeviceError
+from .terminal import Terminal, get_model, get_keyboard_description
 from .tn3270 import TN3270Session
 
 # VT100 emulation is not supported on Windows.
@@ -40,34 +40,35 @@ def _get_keymap(_args, keyboard_description):
     return KEYMAP_3278_TYPEWRITER
 
 def _create_device(args, interface, device_address, _poll_response):
-    # Read the terminal identifiers.
     (terminal_id, extended_id) = get_ids(interface, device_address)
 
-    logger.info(f'Terminal ID = {terminal_id}')
+    logger.info(f'Terminal ID = {terminal_id}, Extended ID = {extended_id}')
 
     if terminal_id.type != TerminalType.CUT:
         raise UnsupportedDeviceError('Only CUT type terminals are supported')
 
-    logger.info(f'Extended ID = {extended_id}')
+    model = get_model(terminal_id, extended_id)
 
-    if extended_id is not None:
-        logger.info(f'Model = IBM {extended_id[2:6]} or equivalent')
+    if model is not None:
+        logger.info(f'Model = IBM {model} or equivalent')
 
-    keyboard_description = get_keyboard_description(terminal_id, extended_id)
-
-    logger.info(f'Keyboard = {keyboard_description}')
-
-    # Read the terminal features.
     features = get_features(interface, device_address)
 
+    # The 3179 includes an EAB but does not respond to the READ_FEATURE_ID
+    # command.
+    if model == '3179':
+        features[Feature.EAB] = 7
+
     logger.info(f'Features = {features}')
 
-    # Get the keymap.
+    keyboard_description = get_keyboard_description(terminal_id, extended_id)
+
+    logger.info(f'Keyboard = {keyboard_description}')
+
     keymap = _get_keymap(args, keyboard_description)
 
     logger.info(f'Keymap = {keymap.name}')
 
-    # Create the terminal.
     terminal = Terminal(interface, device_address, terminal_id, extended_id, features, keymap)
 
     return terminal

oec/device.py

@@ -34,8 +34,8 @@ def execute(self, commands):
         """Execute one or more commands."""
         return self.interface.execute(address_commands(self.device_address, commands))
 
-    def execute_jumbo_write(self, data, create_first, create_subsequent, first_chunk_max_length_adjustment=-1):
-        """Execute a jumbo write command that can be split."""
+    def prepare_jumbo_write(self, data, create_first, create_subsequent, first_chunk_max_length_adjustment=-1):
+        """Prepare a jumbo write command that can be split."""
         max_length = None
 
         # The 3299 multiplexer appears to have some frame length limit, after which it will
@@ -55,7 +55,7 @@ def execute_jumbo_write(self, data, create_first, create_subsequent, first_chunk
         if len(commands) > 1 and logger.isEnabledFor(logging.DEBUG):
             logger.debug(f'Jumbo write split into {len(commands)}')
 
-        return self.execute(commands)
+        return commands
 
 class UnsupportedDeviceError(Exception):
     """Unsupported device."""
@@ -111,65 +111,6 @@ def get_features(interface, device_address):
 
     return parse_features(ids, commands)
 
-def get_keyboard_description(terminal_id, extended_id):
-    is_3278 = extended_id is None or not int(extended_id[0:2], 16) & 0x80
-
-    if is_3278:
-        description = '3278'
-
-        id_map = {
-            0b0001: 'APL',
-            0b0010: 'TEXT',
-            0b0100: 'TYPEWRITER-PSHICO',
-            0b0101: 'APL',
-            0b0110: 'TEXT',
-            0b0111: 'APL-PSHICO',
-            0b1000: 'DATAENTRY-2',
-            0b1001: 'DATAENTRY-1',
-            0b1010: 'TYPEWRITER',
-            0b1100: 'DATAENTRY-2',
-            0b1101: 'DATAENTRY-1',
-            0b1110: 'TYPEWRITER'
-        }
-
-        if terminal_id.keyboard in id_map:
-            description += '-' + id_map[terminal_id.keyboard]
-
-        return description
-
-    id_ = int(extended_id[0:2], 16) & 0x1f
-
-    is_user = int(extended_id[0:2], 16) & 0x20
-
-    if is_user:
-        description = 'USER'
-
-        if id_ in [1, 2, 3, 4]:
-            description += f'-{id_}'
-
-        return description
-
-    is_ibm = not int(extended_id[6:8], 16) & 0x80
-
-    description = 'IBM' if is_ibm else 'UNKNOWN'
-
-    is_enhanced = int(extended_id[6:8], 16) & 0x01
-
-    if is_enhanced:
-        if id_ == 1:
-            return description + '-ENHANCED'
-
-        return None
-
-    if id_ == 1:
-        return description + '-TYPEWRITER'
-    elif id_ == 2:
-        return description + '-DATAENTRY'
-    elif id_ == 3:
-        return description + '-APL'
-
-    return None
-
 def _jumbo_write_split_data(data, max_length, first_chunk_max_length_adjustment=-1):
     if max_length is None:
         return [data]

oec/display.py

@@ -175,12 +175,18 @@ def _load_address_counter(self, address, force_load):
         return True
 
     def _write_data(self, data):
-        self.terminal.execute_jumbo_write(data, WriteData, Data, -1)
+        self.terminal.execute(self.terminal.prepare_jumbo_write(data, WriteData, Data, -1))
 
     def _eab_write_alternate(self, data):
+        # The EAB mask on a 3179 terminal appears to get reset regularly resulting
+        # in the EAB buffer not being updated correctly. This does not affect
+        # later terminals, loading the mask here for all terminals is simpler.
+        #
         # The EAB_WRITE_ALTERNATE command data must be split so that the two bytes
         # do not get separated, otherwise the write will be incorrect.
-        self.terminal.execute_jumbo_write(data, lambda chunk: EABWriteAlternate(self.eab_address, chunk), Data, -2)
+        commands = [EABLoadMask(self.eab_address, 0xff), *self.terminal.prepare_jumbo_write(data, lambda chunk: EABWriteAlternate(self.eab_address, chunk), Data, -2)]
+
+        self.terminal.execute(commands)
 
 def _split_address(address):
     if address is None:

oec/terminal.py

@@ -81,3 +81,75 @@ def sound_alarm(self):
     def load_control_register(self):
         """Execute a LOAD_CONTROL_REGISTER command."""
         self.execute(LoadControlRegister(self.control))
+
+def get_model(terminal_id, extended_id):
+    if extended_id is None:
+        return None
+
+    model = extended_id[2:6]
+
+    # The 3179 does return an extended ID, but it does not include the model
+    # like later terminals.
+    if model == '0000':
+        model = '3179'
+
+    return model
+
+def get_keyboard_description(terminal_id, extended_id):
+    is_3278 = extended_id is None or not int(extended_id[0:2], 16) & 0x80
+
+    if is_3278:
+        description = '3278'
+
+        id_map = {
+            0b0001: 'APL',
+            0b0010: 'TEXT',
+            0b0100: 'TYPEWRITER-PSHICO',
+            0b0101: 'APL',
+            0b0110: 'TEXT',
+            0b0111: 'APL-PSHICO',
+            0b1000: 'DATAENTRY-2',
+            0b1001: 'DATAENTRY-1',
+            0b1010: 'TYPEWRITER',
+            0b1100: 'DATAENTRY-2',
+            0b1101: 'DATAENTRY-1',
+            0b1110: 'TYPEWRITER'
+        }
+
+        if terminal_id.keyboard in id_map:
+            description += '-' + id_map[terminal_id.keyboard]
+
+        return description
+
+    id_ = int(extended_id[0:2], 16) & 0x1f
+
+    is_user = int(extended_id[0:2], 16) & 0x20
+
+    if is_user:
+        description = 'USER'
+
+        if id_ in [1, 2, 3, 4]:
+            description += f'-{id_}'
+
+        return description
+
+    is_ibm = not int(extended_id[6:8], 16) & 0x80
+
+    description = 'IBM' if is_ibm else 'UNKNOWN'
+
+    is_enhanced = int(extended_id[6:8], 16) & 0x01
+
+    if is_enhanced:
+        if id_ == 1:
+            return description + '-ENHANCED'
+
+        return None
+
+    if id_ == 1:
+        return description + '-TYPEWRITER'
+    elif id_ == 2:
+        return description + '-DATAENTRY'
+    elif id_ == 3:
+        return description + '-APL'
+
+    return None

tests/test_device.py

@@ -8,7 +8,7 @@
 import context
 
 from oec.interface import InterfaceWrapper
-from oec.device import address_commands, format_address, get_ids, get_features, get_keyboard_description, _jumbo_write_split_data
+from oec.device import address_commands, format_address, get_ids, get_features, _jumbo_write_split_data
 
 from mock_interface import MockInterface
 
@@ -161,27 +161,6 @@ def test_eab_feature(self):
         # Assert
         self.assertEqual(features, { Feature.EAB: 7 })
 
-class GetKeyboardDescriptionTestCase(unittest.TestCase):
-    def test(self):
-        CASES = [
-            (10, None, '3278-TYPEWRITER'),
-            (0, 'c1347200', 'IBM-TYPEWRITER'),
-            (10, '41347200', '3278-TYPEWRITER'),
-            (0, 'c2347200', 'IBM-DATAENTRY'),
-            (0, 'c3347200', 'IBM-APL'),
-            (0, 'c1348301', 'IBM-ENHANCED'),
-            (0, 'e1347200', 'USER-1'),
-            (0, 'e4347200', 'USER-4')
-        ]
-
-        for (keyboard, extended_id, expected_description) in CASES:
-            with self.subTest(keyboard=keyboard, extended_id=extended_id):
-                terminal_id = TerminalId(0b0000_0100 | (keyboard << 4))
-
-                description = get_keyboard_description(terminal_id, extended_id)
-
-                self.assertEqual(description, expected_description)
-
 class JumboWriteSplitDataTestCase(unittest.TestCase):
     def test_no_split_strategy(self):
         for data in [bytes(range(0, 64)), (bytes.fromhex('00'), 64)]:

tests/test_terminal.py

@@ -7,7 +7,7 @@
 
 from oec.interface import InterfaceWrapper
 from oec.device import UnsupportedDeviceError
-from oec.terminal import Terminal
+from oec.terminal import Terminal, get_keyboard_description
 from oec.display import Display, StatusLine
 from oec.keymap_3278_typewriter import KEYMAP
 
@@ -75,6 +75,27 @@ def test_with_enable_keyboard_clicker_queued(self):
         # Act and assert
         self.assertEqual(self.terminal.get_poll_action(), PollAction.ENABLE_KEYBOARD_CLICKER)
 
+class GetKeyboardDescriptionTestCase(unittest.TestCase):
+    def test(self):
+        CASES = [
+            (10, None, '3278-TYPEWRITER'),
+            (0, 'c1347200', 'IBM-TYPEWRITER'),
+            (10, '41347200', '3278-TYPEWRITER'),
+            (0, 'c2347200', 'IBM-DATAENTRY'),
+            (0, 'c3347200', 'IBM-APL'),
+            (0, 'c1348301', 'IBM-ENHANCED'),
+            (0, 'e1347200', 'USER-1'),
+            (0, 'e4347200', 'USER-4')
+        ]
+
+        for (keyboard, extended_id, expected_description) in CASES:
+            with self.subTest(keyboard=keyboard, extended_id=extended_id):
+                terminal_id = TerminalId(0b0000_0100 | (keyboard << 4))
+
+                description = get_keyboard_description(terminal_id, extended_id)
+
+                self.assertEqual(description, expected_description)
+
 def _create_terminal(interface):
     terminal_id = TerminalId(0b11110100)
     extended_id = 'c1348300'