Measurement Computing Digital488 - Manual (Page 56)

Section 3 Command Descriptions
3.26
Status Un
The Status command (U0) will cause the Digital488 to send the status message when
next addressed to talk. The status of the Digital488 may be read at any time without
interfering with normal operation. Any error conditions are cleared after the status string is
read by the controller. The Status command (Un) also enables the controller to read any single
bit from the I/O ports (U1 through U40).
U0 Send the Digital488 status when next addressed to talk
Un Send the status of bit n (1 thru 40) when next addressed to talk
The format of the status byte returned by the Digital488 after receiving a U0 command
is as follows:
*.*C#E#F#G#I###K#M###P#R#Y#
where each # equals the number corresponding to that command. The leading
information *.* is the revision level of the Digital488 firmware.
Example:
DIM A$[50] dimension A$
CLEAR 718 reset the Digital488
OUTPUT 718;"U0X" send U0 to the Digital488
ENTER 718; A$ read the status byte
DISP A$ display =
1.0C0E0F0G0I000K0M000P0R0Y0
The status returned after receiving a U1 through U40 is an ASCII character '1' or '0',
depending on the level of the line, and the state of the Invert command (I16).
CLEAR 718 reset the Digital488
OUTPUT 718;"U22X" request the status of bit 22
ENTER 718;A$ read the status bit
DISP A$ display shows a 0 (dependent on the signal
applied to the input