Serial Port 3 I/O Path Selection (J13); General-Purpose Software-Readable Header (J14) - Motorola MVME1603 Installation And Use Manual

Serial Port 3 I/O Path Selection (J13)

On the MVME1600-011, serial port 3's I/O signals are routed to backplane
connector P2 and to front panel connector J2. Header J13 determines the
state of the DSR, RI, and TM signals on serial port 3.
With a jumper installed on J13, DSR, RI, and TM come from the front
panel.
With the jumper removed, P2 I/O is selected. The DSR, RI, and TM signals
are not supported in this case, so DSR is held true while RI and TM are
held false.
Jumper On = Front Panel I/O
DSR, RI, and TM from front panel

General-Purpose Software-Readable Header (J14)

Header J14 provides eight readable jumpers. These jumpers can be read as
a register at ISA I/O address $80000801. Bit 0 is associated with header
pins 1 and 2; bit 7 is associated with pins 15 and 16. The bit values are read
as a zero when the jumper is installed, and as a one when the jumper is
removed.
The PowerPC firmware (PPCBug) reserves the four lower-order bits,
SRH3 to SRH0. They are defined as shown in the following list:
J13
2 1
to 8536 device
Hardware Preparation and Installation
J13
2 1
Jumper Off = P2 I/O (factory configuration)
DSR to 8536 device held true
RI and TM to 8536 device held false
1
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