Owner`s manual
18
Mode of Operation 2 provides automatic message multiplexing
between the host port and up to twenty-three peripheral ports. Data
received from the peripheral devices is treated as messages. A
message begins when a peripheral port receives a character from the
device connected to it. A message is completed when the message
terminating character is received or when the buffer is full. Either
condition will result in the message(s) being transferred to the host
device with the Model 24H inserting the peripheral port number prior to
the actual message. Messages will be sent automatically to the host
device in a round-robin fashion (e.g., if the Model 24H is sending a
message from Port 2, Port 3 will be examined next for a complete
message, then Port 4, etc.).
NOTE: The host device may select and transmit data to any peripheral
port while simultaneously receiving all messages from all peripheral
ports.
Mode of Operation 3 provides message multiplexing to the host port of
single messages from all peripheral ports upon request from the host
device. A single message from all ports is sent to the host device only
when a command is received from the host device. The command for
requesting a single message from all peripheral ports is the port select
code ($SELECT default) followed by ASCII capital
S
, and a terminating
character (0A Hex -
Carriage Return
or 0D Hex -
Line Feed
). If there
are no messages, the host port will send a
Line Feed
character to the
host device.
NOTE: The host device may select and transmit data to any peripheral
port while simultaneously receiving single messages from all peripheral
ports.