Terumo CDI 550, Operator'S Manual

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communication with other devices appendix c C-18
CDI Pump Interface Packet Structure.
The format of the packet will be:
<STX>ABBLLLLCSD...DZZ<ETX>
where:
<STX> Start of packet character, which will be character 0x02 (binary, not
ASCII ‘2’).
A Single Character defining the device ID. See Device ID section for
details.
BB 8-bit ASCII hex-encoded sequence value.
LLLL 16-bit ASCII hex-encoded length value. Length is calculated as the
length of the entire packed from the <STX> to the <ETX> inclusive.
C Single ASCII character Command. This will define the major cat-
egory for the packet. See the Command list section for definitions.
S Single ASCII number SubCommand. This will define the specific
request or action under the category of the previously defined Com-
mand character. See the SubCommand list section for definitions.
D...D Variable-length data field in ASCII format. The data field will be
used to pass parameters if necessary. If no data is necessary, this
field will be omitted.
ZZ 8-bit ASCII hex-encoded CRC. This CRC is calculated using the
entire packet up to, but not including, the CRC field. Refer to the
CRC calculation section for how to calculate the CRC.
<ETX> End of packet character, which will be character 0x03 (binary, not
ASCII ‘3’ ).
Device IDs.
Device IDs are single ASCII characters denoting specific device types for communica-
tion. Although the CDI System 550 does not connect with more than one device on
the Pump Interface port, specifying a device type may benefit other devices that do
have multiple connections.
„ The Device ID chosen for the CDI System 550 is ‘X’. All outgoing packets from
the CDI System 550 will have an ‘X’ in the Device ID field.
„ All pumping systems connected to the CDI System 550 are capable of provid-
ing arterial flow. Since no benefit is gained by requiring each pumping system
to have a unique ID, all incoming packets are required to have a device ID of ‘A’ ,
denoting an Arterial Pump.