How to interface the KBD300A keyboard to the CM6700 matrix for ASCII communication
Delay of standard communication for keyboard over fiber to matrix
The KBD300A keyboard with CM6700 matrix offers the feature of ASCII communication. ASCII (American Standard Code for Information Interchange) is a character encoding scheme that represents text communication between devices (computers, etc).
Here’s how the system works when directly wired: The CM6700 sends commands over and over to the keyboards. The keyboards wait for the ready command from matrix and then reply with a response. The communication response time of keyboard to matrix is what determines if the setup will properly function or not. If the system components (KBD with matrix) do not reply within a timely manner to each other, the KBD300A will display a “01” for its red LED display and not function.
REMOTE KEYBOARD INSTALLATION over media
ASCII mode of operation for the keyboard to matrix is often recommended for successful communication over fiber. This is mainly to address response delays that may or may not occur over fiber media of any type (multimode, singlemode).
Configuring the KBD300A in ASCII (non-polled mode) allows the keyboard to send commands at the moment the keyboard is ready to send them. Keyboard does not await a ready status for receipt of command from matrix.
PROGRAM COM 2 OF THE CM6700
- View menu tree navigation tree here: CM6700 COM 2
- Press the PGM key. The Password screen appears.
- Make sure the language selection is English
- Use the number keypad to enter the password – default is 2899100
- Press the ACK key. The Main Menu appears.
- Press 5. The Ports screen appears.
- Using the joystick, move down to COM 2 PORT
- Pan right.
- Use the F1 and F2 to toggle baud rate to 9600
- Move down to the PARITY field and toggle to ODD
- Move down to STOP BITS field and toggle to 1
- Move down to RETURN field and Pan right.
Return to Main Menu and press 9 to exit.
CONFIGURE CM6700 INTERNAL SWITCHES FOR RS422
Note: The CM6700 is configured at the factory for RS422. Configuration of the switch settings will not be required.
- Remove the cover (view cover removal here)
- Set DIP switch SW5 (COM 2) for RS422. (view SW5 switch location here)
CONFIGURE AND WIRE KBD300A FOR ASCII MODE
- Switch Set the KBD300A for ASCII operation mode: See LL#10565
- Wire KBD300A through KBDKIT to COM 2 of CM6700.
- Apply power to the CM6700 (if no already powered). To initialize the keyboard, wait five seconds after power-up, enter the number for the monitor you are viewing (1-4), and press MON. The LED display shows the number entered.
Once you apply power to the keyboard and the CM6700, you can use the keyboard in the same manner as a normal keyboard except that in ASCII Mode you cannot program the CM6700.