Pressure Systems 98RK-1 Command c- Sub-command Index 00 Configure a Host Delivery Stream, Packet

Pressure Systems, Inc. 98RK-1 & 9816 User’s Manual©

Command 'c'— Sub-command Index 00: Configure a Host Delivery Stream

This sub-command is used to configure the parameters of each of the three possible concurrent host delivery streams, one at a time. Following this configuration phase, the stream (1, 2, or 3) may be started and stopped with other sub-commands. The sub-command’s format is:

“c 00 st [[[[p]p]p]p]p sync per f num”

Command

‘c’ is the command letter.

‘00’ is the sub-command index (ii) for configuration.

‘st’ is the stream id digit (1, 2, or 3).

‘ppppp’ is a 1-5 digit hex position field (channel selection bit map), capable of selecting 1-18 external/internal channels.

‘sync’ is sync type (0=hardware trigger or 1=clock).

‘per’ is the period (if sync=0: # of trigger periods or if sync=1: delay timer period in msec).

‘f’ is the format of each acquired datum in stream.

‘num’ is the number of packets delivered in stream (0=unlimited/continuous).

	NOTE: all parameters are separated by a space.
Response	“A”
	‘A’ is the acknowledge letter
Autonomous	none generated
Packet

Description: Configures a particular stream (‘st’) to deliver data packets autonomously to the Configures a particular stream (st) to deliver data packets autonomously to the host, with each packet containing selected acquired data for the channels specified. These channels are specified by a bit map (4-20-bits) encoded as a 1- 5 hex digit position field (ppppp as described in Section 3.1.3.3). A separate sub- command (ii=05) may be used to select which acquired data are included in each stream. By default, only Pressure EU Data are selected (if ii=05 sub-command never executed for stream).

The individual data packets of the stream may be synchronized with either an external (user-supplied) hardware trigger or a periodic clock interrupt generated inside each module. This choice is made with the sync type (sync) parameter (a single digit) where: 0 = synchronize with hardware trigger; 1= synchronize with periodic software clock.

When the hardware trigger is used to synchronize data output (sync = 0), it is assumed that the user would prefer to also synchronize the internal data acquisition cycle. For this reason, when a stream utilizing hardware trigger is started, the module firmware switches out of the free-running continuous data acquisition mode described earlier. Instead, the Model 9816 waits in an idle mode until a hardware trigger is received to initiate a host stream output. Only on the receipt of that hardware trigger will the module scan and EU convert all

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