Kepco MST 488 Programmer Manuel d'utilisateur télécharger pdf (Page 28)

3-2

MST488-27 013004

3.2.1 STRING PARSING

When the MST 488-27 is in listen mode, strings are accepted. When the host controller sends

the last byte it can assert the EOI line to indicate the string is complete. The GPIB listener func-

tion automatically adds a LF to terminate the string input. The parsing software then processes

the string and if there are valid commands, the power supply is updated with the new control

input. Some GPIB host controllers do not have the ability to assert the EOI control line, however

the GPIB listener function will also terminate the string input when either a carriage return (0d

)

or Line Feed (0A

) character is received.

TABLE 3-2. IEEE 488 (GPIB) BUS COMMAND MODE MESSAGES

MNEMONIC MESSAGE DESCRIPTION COMMENTS

ATN Attention Received

DAC Data accepted Received or Sent

DAV Data Valid Received or Sent

DCL Device Clear Received

IFC Interface Clear Received

MLA My Listen Address Received

MTA My Talk Address Received

OTA Other Talk Address Received

RFD Ready for Data Received or Sent

SDC Selected Device Clear Received

SPD Serial Poll Disable Received

SPE Serial Poll Enable Received

SRQ Service Request Sent

UNL Unlisten Received

UNT Untalk Received

TABLE 3-3. IEEE 488 (GPIB) BUS DATA MODE MESSAGES

MNEMONIC MESSAGE DESCRIPTION COMMENTS

DAB

Data Byte Received or Sent

END

End Received or Sent

EOS

End of String Received or Sent

RQS

Request Service Sent

STB

Status Byte Sent

1 2 ... 23 24 25 26 27 28 29 30 31 32 33 ... 67 68

Pas de commentaire

Kepco MST 488 Programmer Manuel d'utilisateur Page 28