MagTek MICR Plus RS-232 - Manual (Page 22)

MICR PLUS, RS-232
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Table 4-3. Control Characters
CONTROL
CHARACTER DESCRIPTION HEX VALUE
<STX> Start of Text 02
<ESC> Escape 1B
<ETX> End of Text 03
<CR> Carriage Return 0D
<LF> Line Feed 0A
For example, if <STX> and <CR> are set to YES, the message from the MICR Plus will look
like this:
MICR Data: <STX>data<CR>
Control Characters and Card Data
The control characters are also available for card data but their position on the message is
controlled by the Card Data Message parameter (see SWC Command, below). For example, if
the <STX> and <ETX> options are set to YES, the message may be transmitted as follows:
If Multiple Message: <STX>[TK1]<ETX><STX>[TK2]<ETX><STX>[TK3]<ETX>
If Single Message:
<STX>[TK1] [TK2] [TK3]<ETX>
Communication Modes
The selection of Comm Modes is a quick way of selecting multiple Control Characters. For
instance, to send a carriage return/line feed pair after the data, you can specify Comm Mode 3.
Comm Mode 7, also known as Packet Mode, calculates an LRC (Longitudinal Redundancy
Check), and appends it to the data message. Also, if a <NAK> (hex 15) character is received in
this mode, the MICR Plus will resend the last message.
Send Data After Error
The request Send Data After Error specifies whether the MICR Plus will return data to the host
after a read error. If YES is selected and the MICR Plus reads a check with an error, the MICR
Plus will send the data back to the host. If NO is selected and the MICR Plus finds an error, it
will discard the data and nothing will be sent. The error conditions are listed in Table 4-4.