TOHO ELECTRONICS TTX-700 - Manual (Page 12)

⑧ ACK
It is an acknowledge code. If a message received by this product is error-free, this code will
be incorporated in the "response message" from this product and returned.
⑨ NAK
It is a negative acknowledge code. If a "request message" received by this product is
error-ridden, this code will be incorporated in the "response message" from this product and
returned.
If the "request message" received is error-ridden, the error contents (⑩ ERR type) will be
incorporated in the "response message" from this product, following NAK.
⑩ ERR type
If a "request message" received from this product is error-ridden, the error contents (either
of the numbers in the table below) will be incorporated in the "response message" from this
product, following "⑨ NAK."
The error number 0 is an instrument error (memory error or A/D conversion error). It will
be incorporated in the "response message" regardless of whether there is an error in the
"request message."
The error number 9 is an AT error. It will therefore be incorporated in the "response
message" regardless of whether there is an error in the "request message." Remove the
cause of the error immediately and start the AT again.
If there are two or more errors occurring at the same time, the largest error number will be
incorporated.
The table below indicates the error contents and classifications.
Error No. Error contents in the "request message" received by this product
0 Instrument error (memory error or A/D conversion error)
1 The numerical data deviated from the "range of settings designated specifically with setting
items."
2 The change of requested items is disabled or there are no items to be read.
3 An ASCII code other than the numerical data was specified in the field of numerical data.
An ASCII code other than numbers and "-" was specified in the field of codes.
4 Format error
5 BCC error
6 Overrun error
7 Framing error
8 Parity error
9 A PV error occurred during AT. Or AT will not end 3 hours later.
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