Sutter Instrument Lambda 10-3, Operation Manual

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LAMBDA 10-3 OPERATION MANUAL – REV. 3.03 (20110829)
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by
port
reads as the indicated by data expressions. The AND
data
expression is evaluated as
an AND operation. Thus, we may test to see if the BUSY line is set as follows:
WAIT 889, 128
The program will suspend operation until the value read for the most significant bit is 1.
Since the printer adapter inverts this bit, this condition will be met only when the BUSY line
is low. An XOR operation can be used as well, as noted in the Microsoft QuickBASIC
Language Reference. The WAIT statement will XOR the read data before the AND operation
if a value for XORdata is provided. Consider the statement:
WAIT 889, 128, 128
The XOR of the read value of the port with 128 will invert the most significant bit. The
program execution would thus be suspended until the BUSY signal went high, indicating
that the unit was busy. Using the 2 statements in series would insure that the controller had
time to assert the BUSY line in response to a command before the program began to test to
see if the BUSY line had come back down:
WAIT 889, 128, 128
WAIT 889, 128,
AN IMPORTANT CONSIDERATION WHEN USING THE WAIT STATEMENT:
AN IMPORTANT CONSIDERATION WHEN USING THE WAIT STATEMENT: AN IMPORTANT CONSIDERATION WHEN USING THE WAIT STATEMENT:
AN IMPORTANT CONSIDERATION WHEN USING THE WAIT STATEMENT: The
WAIT statement seems to be ideal because it provides a fast and easy way of directly testing
input port bits. However, if the input port does not have the correct value, and you are
unable to force the port to the correct value, you will need to reboot the computer. This
should not be a significant problem in routine operation of a system, but it can provide
considerable frustration when developing and testing the control program. Test the WAIT
function with simple programs before you use it. Make sure that you will not lose important
data if you are forced to reboot.
8.6
8.6 8.6
8.6 Dedicated TTL Line
Dedicated TTL Line Dedicated TTL Line
Dedicated TTL Line
Unlike the commands through the 8 bit port, the direct logic input lines will act even if the
BUSY
BUSY BUSY
BUSY line is active. However, these lines only provide the conditional opening: the shutter
will open while the wheel is stopped. It follows that the only advantage of the direct control
lines is that, in a two-shutter system, the shutter associated with a wheel that was not
moving could be opened or closed while the other wheel is moving. When the controller is in
the manual mode, the dedicated TTL lines are ignored. If a valid 8-bit shutter command has
been received by the controller, the dedicated TTL lines are ignored until the controller is
reset.
The dedicated input lines are at pins 14 and 16 of the 25-pin parallel connector. Shutter A is
opened by setting pin 14 high and closed by setting pin 14 low. Shutter B is opened by setting
pin 16 high and closed by setting pin 16 low. Remember that this is a conditional opening:
the shutter will be open only if the corresponding wheel is not moving.
If the 25-pin connector is brought to a PC parallel adapter, pins 14 and 16 correspond to the
AUTOFEED and INITIALIZE control lines for a printer. These lines are controlled by
setting bits in the command port of the printer adapter, which is at an address that is equal
to the base port a 2.
Pin 14 corresponds to the bit that encodes the value 2 and pin 16 corresponds to the bit that
encodes the value 4. Sending a value of 2 to this port will set pin 14 low, which closes the