Special Pull Resistor Disable Control Functionality (Sprds); Pull Device Select (Pull_Sel); Signal Reset States - Motorola MPC533 Reference Manual

Reset State
2.6.4.3

Special Pull Resistor Disable Control Functionality (SPRDS)

For the signals that support debug and opcode tracking functionality, the pull resistors will
be controlled by the SPRDS bit in the PDMCR register. During reset this signal will be
synchronously used to enable the pull resistors in the pads. On negation of reset, based on
which functionality is selected for the signals, this signal is set to disable the pull resistors,
or is continued to be held in its reset state to indicate that the pulls are disabled only when
the output driver is enabled.
2.6.4.4

Pull Device Select (PULL_SEL)

The MIOS14 signals have selectable pull-up or pull-down devices. The devices are
controlled by the PULL_SEL signal. A high on the PULL_SEL signal enables pull-up
devices on the MIOS14 signals. A low enables pull-down devices. Note that the pull
devices can be disabled by the PULL_DIS[0] (MIOS14) bits in the PDMCR register. See
Section 2.3, "Pad Module Configuration Register (PDMCR)."
2.6.5

Signal Reset States

Table 25-15 summarizes the reset states of all signals on the . Note that PD refers to a weak
pull-down, PU2.6 refers to a weak pull-up to 2.6 V, and PU5 refers to a weak pull-up to 5
V. All control of the weak-pull devices is in the pad module configuration register,
described in Table 2-5.
2.6-V inputs are 5-V tolerant, but 2.6-V outputs are not. Do not
connect 2.6-V outputs to a driver or pull-up greater than 3.1 V.
Depending on the application, pins may require a pull-down
resistor to avoid getting any command due to noise.
2-28
PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
NOTE
NOTE
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