System information

SECTION TWO - FRONT PANEL OPERATION
recognize commands over either the RS-232 or CLK/DATA interface. Whenever a valid
command with no error is received over the RS-232 interface, it will start transmitting over the
RS-232 interface and not the CLK/DATA interface.
In like fashion, it is possible to switch back to the CLK/DATA interface. Whenever a valid
command with no error is received over the CLK/DATA interface, it will start transmitting over
the CLK/DATA interface and not the RS-232 interface.
Since the RS-232 interface is not as interlocked as the CLK/DATA interface, the following
additional requirements are placed on the RS-232 protocol.
1. The system is allowed to send commands only in response to transmissions set by the
keyboard.
2. When the keyboard transmits it will wait for the transmission to be complete and then
delay another two milliseconds before again checking the keystroke buffer. This delay
allows the system time to send a resend command or other command such as turning on a
light. Since transmitting a character takes approximately one millisecond at 9600 baud,
this allows about 1 millisecond processing time for the system.
3. To allow the system a chance to send out commands, the keyboard will send out a strobe
signal periodically. The strobe signal is simply the character EAh. This character will be
transmitted if the keyboard is otherwise idle for approximately 30 milliseconds. The
system can then send out a command in response to the strobe instead of having to wait
until the next keystroke.
Hardware and Software Requirements
The serial keyboard requires a REV E keyboard controller card with firmware version #1.21 or
greater. Firmware for the REV E cards cannot be used with older revision cards and vice versa.
CNC software must be of version # *.86 or greater.
The serial keyboard uses COM2. Therefore, if the serial keyboard is used, the secondary serial
port parameter should be set to none. The secondary serial port parameter may be removed in a
future version.
On machines set up to use the serial keyboard there will be a revised cable in the mag box.
Previously, the cable coming in was split in two and ran to the video card and to the controller
card. Now the cable will split in three and have a 9-pin D-Sub connector to attach to the I/O card.
The connector on the I/O card should be set up to be COM2 (as shipped to us, it is
usually COM1).
Enabling the Serial Keyboard
The CNC program will use the serial keyboard interface if the power-up parameter Serial
Keyboard is set to Yes and if the program is executed without any command line options.
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