ATAM893X-TKHYZ ATMEL [ATMEL Corporation], ATAM893X-TKHYZ Datasheet - Page 25

• Manufacturer Part Number: ATAM893X-TKHYZ
• Description: Flash Version for ATAR080, ATAR090/890 and ATAR092/892
• Manufacturer: ATMEL [ATMEL Corporation]

5.2.2
4680C–4BMCU–01/05
Bi-directional Port 2
Figure 5-2.
As all other bi-directional ports, this port includes a bit-wise programmable Control Register
(P2CR), which enables the individual programming of each port bit as input or output. It also
opens up the possibility of reading the pin condition when in output mode. This is a useful fea-
ture for self testing and for serial bus applications.
However, Port 2 has an increased drive capability and an additional low resistance pull-up/-
down transistor mask option.
Note:
Master reset
OUT
IN
I/O Bus
Care should be taken connecting external components to BP20/NTE. During any reset phase, the
BP20/NTE input is driven towards V
must not be pulled down (active or passive) to V
ing a resistor of less than 150 k . This prevents the circuit from unintended switching to test mode
enable through the application circuitry at pin BP20/NTE. Resistors less than 150 k might lead to
an undefined state of the internal test logic, thus disabling the application firmware.
To avoid any conflict with the optional internal pull-down transistors, BP20 handles the pull-down
options in a different way than all other ports. BP20 is the only port that switches off the pull-down
transistors during reset.
Bi-directional Port 1
(Direction)
(Data out)
D
P1DATy
S
R
Reset
R
NQ
Q
Q
DD
by an additional internal strong pull-up transistor. This pin
(1)
Flash options
SS
during reset by any external circuitry represent-
(1)
(1)
Switched
pull-up
V
DD
(1)
(1)
Switched
pull-down
V
DD
ATAM893-D
Static
pull-up
BP1y
Static
pull-down
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