HP 83751A Programming Manual page 234

Error Messages
-144 Character data too long
The character data element contains more than twelve characters
(see IEEE 488.2, 7.7.1.4).
Character data not allowed
A legal character data element was encountered where prohibited
by the device.
-150 String data error
This error, as well as errors - 151 through - 159, are generated
when parsing a string data element. This particular error message
should be used if the device cannot detect a more specific error.
-151 Invalid string data
A string data element was expected, but was invalid for some
reason (see IEEE 488.2, 7.7.5.2); for example, an END message
was received before the terminal quote character.
String data not allowed
-158
A string data element was encountered but was not allowed by the
device at this point in parsing.
Block data error
-160
This error, as well as errors -161 through - 169, are generated
when parsing a block data element. This particular error message
should be used if the device cannot detect a more specific error.
Invalid block data
-161
A block data element was expected, but was invalid for some
reason (see IEEE 488.2, 7.7.6.2); for example, an END message
was received before the length was satisfied.
-168 Block data not allowed
A legal block data element was encountered but was not allowed
by the device at this point in parsing.
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