Panasonic JB-3300 Technical Manual page 231

(c) Description of 8255A-5
The 8255A-5 is a programmable general-purpose I/O device incorporat-
ing 3 I/O ports (each 8 bits). It is used to internally and
externally feed a variety of data via the Program Control Operation.
Part is connected to the keyboard interface, port to the
speaker unit, keyboard, and the DIP switch interface, and port to
the DIP switch interface, respectively. For more details, refer to
the data sheet.
(d) Short plug setting
The short plugs on the CPU and I/O boards are set as follows when the
equipment is shipped.
On the CPU board
J7 «2... EP Short
JB ...e. EP Short
Jil .... UNDE Short
J13 .... with expansion memory Short
without expansion memory Open
On the I/O board
J2 .aeee 232C Short
J3 ..... 378H Short
Ja .ccee 3F8H Short
JSD seco FD version Short
HD version Open
J6 ..... IROQ4 Short
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