
28
56F8355 Technical Data
Preliminary
RESET
78
Schmitt
Input
Reset — This input is a direct hardware reset on the
processor. When RESET is asserted low, the device is
initialized and placed in the reset state. A Schmitt trigger
input is used for noise immunity. The internal reset signal
will be deasserted synchronous with the internal clocks
after a fixed number of internal clocks.
To ensure complete hardware reset, RESET and TRST
should be asserted together. The only exception occurs in
a debugging environment when a hardware device reset is
required and the JTAG/EOnCE module must not be reset.
In this case, assert RESET but do not assert TRST.
Note: The internal Power-On Reset will assert on initial
power-up.
To deactivate the internal pull-up resistor, set the RESET
details.
RSTO
77
Output
Reset Output — This output reflects the internal reset
state of the chip.
EXTBOOT
Internal
Ground
Schmitt
Input
External Boot — This input is tied to VDD to force the
device to boot from off-chip memory (assuming that the
on-chip Flash memory is not in a secure state). Otherwise,
it is tied to ground. For details, see Table 4-4.
Note: When this pin is tied low, the customer boot software
should disable the internal pull-up resistor by setting the
Note: This pin is internally tied low (to VSS).
EMI_MODE
Internal
Ground
Schmitt
Input
External Memory Mode — This device will boot from
internal Flash memory under normal operation.
This function is also affected by EXTBOOT and the Flash
Note: When this pin is tied low, the customer boot software
should disable the internal pull-up resistor by setting the
Note: This pin is internally tied low (to VSS).
Table 2-2 56F8355 Signal and Package Information for the 128-Pin LQFP
Signal Name
Pin No.
Type
State
During
Reset
Signal Description