Messages
The PPC4E supports a set of commands that are common to all instruments conforming to IEEE Std. 488.2. These command make it easy to perform basic function for any device that supports these commands. These commands also cover the status reporting commands. See Section 4.5 for details on the status registers mentioned in these commands.
Table 22. Program Message List
∗CLS Clear all of the status & event structures.
∗ESE Read or set the Standard Event Status Enable Register. ∗ESR Read the Standard Event Status Register.
∗IDN Identify the PPC4E version, range, and serial number.
∗OPC Set the operation complete bit when all operations have completed. ∗OPT Read the list of installed PPC4E options.
∗RST Reset the PPC4E control settings to factory settings. ∗TST Read the power on self test status.
∗SRE Read or set the Service Request Enable Register. ∗STB Read the Status Byte Register.
∗RSE Read or set the Ready Status Enable Register. ∗RSR Read the Ready Status Register.
5.6.1
Program Message Descriptions
∗CLS
Purpose Clear all of the status & event structures.
Command “∗CLS”
Remarks This program message clears the following events and status registers: Standard Byte Register (STB)
Standard Event Status Register (ESR) Error Queue
Pending OPC operations Example (classic) Sent: Reply: “∗CLS” none ∗ESE
Purpose Read or set the Standard Event Status Enable Register. Command
Query
“∗ESE n” “∗ESE?” Default “∗ESE 0”
Arguments n: ’0 to 255’ This is the decimal representation of the bit(s) to enable. To enable the PON and QYE bits, the argument would be 128 + 4 = 132.
Remarks The Standard Event Status Enable register determines which bits in the standard Event Status Register are enabled and included in the Status Byte Register (ESB bit), and can assert the SRQ line. The reply is in decimal numeric form.
Example (enhanced)
Sent: Query reply:
“∗ESE=128” (enables the PON bit) “128” (no reply if IEEE-488)
Errors ERR# 6: n is not valid.
∗ESR
Purpose Read the Standard Event Register. Command “∗ESR?”
Remarks The Standard Event Register contents are cleared after reading. The reply is in decimal numeric form. Example (enhanced) Sent: Reply: “∗ESR?”
“20” (the QYE and EXE bits are set)
∗IDN
Purpose Identify the PPC4E versions, range, and serial number.
Query “∗IDN?”
Remarks The identification reply is made up of the following comma delimit fields: Manufacturer
The product model Serial number of the PPC4
Serial number of the HI pressure RPT
Serial number of the LO pressure RPT (‘0’ if not installed) PPC4E software version.
CPU board logic version Main board logic version. Example
(enhanced)
Sent:“∗IDN?”
Reply:“DH INSTRUMENTS INC, PPC4E, 123,100951,63041, Ver1.00E, 1.00a,1.00a”
∗OPC
Purpose Sets the operation complete bit when all operations have completed. Command
Query
“∗OPC” “∗OPC?”
Remarks This Command enables the PPC4E to set the OPC bit in the Standard Event Status Register when it has completed all pending functions.
The Query replies with a “1” when all functions are complete. Example (enhanced) Sent: Query reply: “∗OPC” “1”
∗OPT
Purpose Reads the list of installed PPC4E options.
Query “∗OPT?”
Remarks This Query returns any registered option(s) installed in the PPC4. Each option is separated by a comma. If there are no options installed, the reply will be “NONE”
Possible options: “IEEE-488:0” “GUI”
The IEEE-488 option is installed. Indicates PPC4-gui with an LCD Example (enhanced) Sent: Reply: Reply: “∗OPT?” “IEEE-488:0, GUI”
“NONE” (no options installed)
∗RST
Purpose Resets the PPC4E control settings to factory settings. Command “∗RST””
Remarks This Command sets the PPC4E settings to factory settings. This equivalent to a front panel executed RESET/SET. This does not affect the communications settings.
Example (enhanced)
Sent: Reply:
“∗RST”
“∗RST” (no reply if IEEE-488) See Also Section 3.5.4.1, Reset - Sets
∗SRE
Purpose Read or set the Service Request Enable Register. Command
Query
“∗SRE n” “∗SRE?” Default “∗SRE 0”
Arguments n: ’0 to 255’ This is the decimal representation of the bit(s) to enable. To allow the MAV and ESB bits to assert the SRQ line, the argument would be 32 + 16 = 48. Bit 6 (64) is reserved and cannot be set.
Remarks The Service Request Enable Register determines which bits of the Status Byte can set the MSS bit of the Status Byte and request service by asserting the SRQ line of the IEEE-488 interface. Example
(enhanced)
Sent: Query reply:
“∗SRE=48” (enables the MAV and ESB bits) “48” (no reply if IEEE-488)
Errors ERR# 6: n is not valid.
∗STB
Purpose Read the Status Byte Register. Command “∗STB?”
Remarks The Status Byte Register reflects the general status of the PPC4. The ‘MSS’ bit state is represented by bit 6. Example (enhanced) Sent: Reply: “∗STB?”
“80” (The MSS and MAV bits are set)
∗TST
Purpose Read the power on self test status.
Query “∗TST?””
Remarks The PPC4E system memory stores the user settings (units, resolution, generation settings) and retains them when the unit if OFF. On power-up, this memory is checked. If this memory is corrupted, all user settings are reset to default (as if the “∗RST” program message was executed), and the ∗TST query will return a non zero value. If the PPC4E passed the test on power-up OR if the ∗TST query was used at least once since the PPC4E was powered up the reply will be a ‘0’.
Example (enhanced) Sent: Reply: “∗RST?” “1”
*RSE
Purpose Read or set the Ready Status Enable Register. Command
Query
“RSE n” “RSE?”
Default “RSE 0”
Arguments n: ’0 to 255’ This is the decimal representation of the bit(s) to enable. To enable the RDY bit, the argument would be 1.
Remarks The Ready Status Enable Register determines which bits in the Ready Status Register are enabled and included in the Status Byte Register (RSR bit), and can assert the SRQ line. The reply is in decimal numeric form.
Example (enhanced)
Sent: Query reply:
“∗RSE=1” (enables the RDY bit) “1” (no reply if IEEE-488)
Errors ERR# 6: n is not valid.
*RSR
Purpose Read the Ready Status Register.
Command “RSR?”
Remarks The Ready Status Register contents are cleared after reading. The reply is in decimal numeric form. Example (enhanced) Sent: Reply: “RSR?”