Reading status bit from SR830 lockin

[Madhusudan Singh]

Hi

I am using STB? to poll bit 1 of the serial poll status byte to find out if
an issued auto gain (AGAN) command has finished executing.

I find that the data buffer contains some other data and my reads of this
bit are thus not reliable. How do I ensure that the buffer is clear before
STB? 1 is asserted ? It is the first command executed on the lockin, so
there is no reason for any data to be present before this.

Thanks.