Owner`s manual

M SERIES DAC
BASE UNIT AND MODULE OPERATION
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has been received is treated as normal data and is sent to the current selected
port.
OPERATING IN IMMEDIATE MESSAGE MODE
Immediate message mode provides automatic message multiplexing between the
designated host module and all ports on the V74/V75/V87 module. Messages are sent
automatically to the designated host computer in a round-robin fashion a message at a
time. For example, if two V74 modules installed as Module 2 and Module 3 are
sending messages from all ports to the same designated host module, a message from
Module 2 Port 1 is sent to the designated host module followed by a message from
Module 3 Port 1 followed by a message from Module 2 Port 2 followed by a message
from Module 3 Port 2, and so on.
NOTE: The designated host computer can select and transmit data to any
serial port while simultaneously receiving messages from all ports. A
terminal connected to a non-designated host module can select and send data
to any port. However, messages are sent to the designated host terminal
only. If a connection exists between a host module and the desired port, the
requesting host module is sent a busy message.
If a designated host module is currently receiving messages and the host computer
selects a port on a V74/V75/V87 operating in immediate or command mode, the
messages continue to be sent to the host computer. If the host computer selects a port
on a module operating in full duplex mode while receiving messages, the messages
stop until the host computer disconnects. If the host computer selects a module
operating in command mode while receiving messages, messages continue to be sent
until the host issues a data command (not CBn<cr>). The messages do not resume
until the host disconnects from the module.
The host module can make a full duplex connection to a serial port when the
peripheral module is operating in full duplex, immediate message, or immediate data
mode by sending the port select code, the peripheral module number, a comma, the
peripheral port number, Capital "F", and <cr>.
For example, if the default port select code is used ($BT) and the peripheral module is
installed as Module 2, peripheral port 1 is selected for full duplex communication by
sending $BT2,F<cr>.
The host module remains in full duplex communication with Module 2, Port 1, until a
disconnect is sent ($BT<cr>) or a different port is selected. When a disconnect
command is sent, the peripheral module reverts back to the previous mode of
operation.