Bay Technical Associates 525H User Manual
16
To clear the receive buffer for a selected peripheral port, send the
control character followed by ASCII capital R. All complete or partial
messages in the buffer of the selected peripheral port will be erased
regardless of the mode of operation.
control character followed by ASCII capital R. All complete or partial
messages in the buffer of the selected peripheral port will be erased
regardless of the mode of operation.
In Mode of Operation 1, the H-Series multiport will provide full duplex
communication between the host port and the selected peripheral
port. Port 2 is the selected peripheral port when the multiport powers
up. The host port and the selected peripheral port will remain
connected until another peripheral port is selected. Data received by
non-selected peripheral devices will be stored in the multiport's buffer
and sent to the host device when the peripheral port is selected.
communication between the host port and the selected peripheral
port. Port 2 is the selected peripheral port when the multiport powers
up. The host port and the selected peripheral port will remain
connected until another peripheral port is selected. Data received by
non-selected peripheral devices will be stored in the multiport's buffer
and sent to the host device when the peripheral port is selected.
When switching ports, there may be some question as to which is the
last character received from the current port and which is the first
character received from the new port. A way to avoid this confusion
when selecting a new port is to wait two character times between
Control-T and the port number. When the multiport receives
Control-T, it stops the input of data to the host UART from the current
port. However, since the UART has some buffer, up to two characters
may still be sent to the host device. The multiport does not start
loading data from the new port into the host UART until the new port
number is received. This delay may be accomplished by sending a
string of ASCII zeros (30 Hex) between
last character received from the current port and which is the first
character received from the new port. A way to avoid this confusion
when selecting a new port is to wait two character times between
Control-T and the port number. When the multiport receives
Control-T, it stops the input of data to the host UART from the current
port. However, since the UART has some buffer, up to two characters
may still be sent to the host device. The multiport does not start
loading data from the new port into the host UART until the new port
number is received. This delay may be accomplished by sending a
string of ASCII zeros (30 Hex) between
Control-T and the new port
number.