GE MDS ORBIT ECR, Техническое руководство

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62 MDS Orbit MCR/ECR Technical Manual MDS 05-6632A01, Rev. F

VMIN == 0; VTIME > 0: If serial data is received, the terminal server will continuously read
the number of bytes available until VTIME has elapsed then process the data.

VMIN > 0; VTIME > 0: Once an initial byte of input becomes available the terminal server
waits until the MIN bytes have been read, or when the inter-byte timeout expires. The timer is
restarted after each further byte is received and because the timer is started only after the initial
byte is received, at least one byte will be read.
Serial Hardware Flow Control
Hardware Flow Control: When operating in CTSKEY mode, all serial ports in the data path are required
to be set to the same baud rate, and that VMIN and VTIME remain at the defaults for serial data packets
less than or equal to 255 bytes. For serial packets over 255 bytes it is recommended that a cts-delay time
of at least 90ms be used to account for the VTIME delay of the over-the-air sending unit.
Hardware Flow Control Modes:
DCE 1.

CTS follows RTS after a programmable CTS delay .

If the unit’s input buffer approaches a full condition it can deassert CTS regardless of state of
RTS.
CTSKEY 2.

Based on legacy MDS devices including TransNET, the device will act similar to a DTE but
will provide signaling on the CTS line instead of the RTS line.

When the first character of a transmission is ready to be sent to the serial port, the unit shall
assert CTS and delay for
CTS delay time expiration before outputting the first character.

After the last character of a transmission is output from the serial port, the unit shall keep CTS
asserted until the expiration of
CTS hold time.
CTSKEYPLUS 3.

The unit shall support flow control (Throttling) on the RTS pin. The device is expected to be
wired via null modem to an external DCE device. The CTS line of the external DCE device
drives the RTS line of the unit.
Outlined Configuration: Orbit MCR: Hardware Flow Control
Configure Serial Port under test for Hardware Flow Control 1.

Configure Hw Flow Control to true

Configure Hw Device Mode: DCE, CTSKEY, CTSKEYPLUS

Configure any remaining parameters, Cts Delay, Cts Hold, VMIN, VTIME
Save/Commit Configuration 2.
Step by step Web based Walkthrough:
On the left hand side of the Web GUI, click Services . 1.
Click Serial from the Services drop down. 2.
Click the Serial Port Name on the Basic Config tab to configure Hardware Flow Control. 3.
NOTE
Cts Hold -The CTS hold parameter is applicable only when h/w device mode = CTSKEY or
CTSKEYPLUS. This parameters specifies the time (in milliseconds) to hold CTS up after data
is transmitted.