IBM 4840-563 System Reference Manual page 67

3-Track MSR data
Incoming data from the 3-track MSR has the following format:
JUCC MSR data
Incoming data from the JUCC MSR has the following format:
Programming
Interface Description
Track data switch
On the 3 track MSR, the track data interface is chosen with a slide switch located on the MSR such that it is
only accessible when the MSR is not attached. One setting of the switch will cause the MSR to send track
data with a serial interface at 19200 baud with 8 bits, no parity and 1 stop bit. The other setting of the slide
switch will cause the MSR to send track data via the PS/2 keyboard interface. A pin button located so that it
is not accessible with the MSR is fully installed is used to reset the MSR's configuration to the factory default
state.
SurePOS 500 Model XX3 Technical Reference, v 1.3 Page 67 of
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