Hypercom M4230 User Manual page 22

Before completing the sale, check that the transaction was approved. If the
transaction is declined, the terminal will beep for two seconds and display an error
message giving the reason. An explanation of the error code is available in Section 10.2,
Response Codes.
Approved Receipt
(approved with PIN, Approved Credit Card Receipt
no signature required) (signature required)
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EFTPOS PROFESSIONAL MOBILE GPRS USER GUIDE TRANSACTION PROCEDURES