A controlcode value of 10
or 11 is used to programmatically change the line speed associated
with a device. Both input and output speeds are affected. The value
passed in param must be expressed in characters
per second (1 character per second = 10 bits per second).
The choices supported by MPE/iX are 30, 120, 240, 480, 960, and
1920. For direct connect devices on DTC 72MX, 3840 is also valid.
These equate to the MPE/iX supported speeds of 300, 1200, 2400,
4800, 9600,19200, and 38400 bits per second. Any other settings
will cause the intrinsic to return a condition code of CCL.
The controlcode values of 10 and 11
function in an identical manner and can be used interchangeably.
The duplication exists because early versions of the HP 3000
(Series II/III) supported a terminal controller (the ATC), which
allowed different speeds to be used for input and output on the
same device. For devices attached to the ATC controller a controlcode
of 10 adjusted the input speed while a controlcode
of 11 adjusted the output speed. Split speeds for input and output
are not supported on MPE/iX.
You must be sure the speed associated with a device matches
the physical speed setting of the device and of the modem if a modem
is part of the connection. If you programmatically change the speed
of a device, your program should request that the speed setting
be manually changed at the device as well.
If either of these FCONTROL calls is issued against a terminal
connected via PAD, DTC Telnet, Telnet/iX, or VT, the call will return
a CCE condition code but will actually have no effect on the speed
at which the device is transmitting. Additionally, the call will
return a meaningless value in param.
When a device is initially opened programmatically, the speed
is set to the default speed of the device. If a device is opened
as a log on device (and the device was configured with speed and
parity sensing enabled), the speed setting is sensed from the speed
of the first carriage return character received. The default speed
of a device is configured through the Node Management Configuration
Manager (NMMGR), or through the OpenView DTC Manager, for networks
managed by an OpenView workstation. You must reconfigure the device
to permanently effect a change to the configured speed.
