AT89LP216 Atmel Corporation, AT89LP216 Datasheet - Page 26

• Manufacturer Part Number: AT89LP216
• Manufacturer: Atmel Corporation

Specifications of AT89LP216

• Flash (kbytes): 2 Kbytes
• Max. Operating Frequency: 20 MHz
• Cpu: 8051-1C
• Max I/o Pins: 14
• Spi: 1
• Uart: 1
• Sram (kbytes): 0.125
• Operating Voltage (vcc): 2.4 to 5.5
• Timers: 2
• Isp: SPI/OCD
• Watchdog: Yes

13.4
13.5
26
Ports During Powerdown
Port Alternate Functions
AT89LP216
Due to the 5V tolerant port structure, the output ports may have reduced V
under DC conditions, i.e. in the powerdown state, and at high temperature. It is recommended
that output ports be placed in a low state, if possible, prior to entering powerdown, or else exter-
nal pull-ups can be used to maintain the output at a higher voltage.
Most general-purpose digital I/O pins of the AT89LP216 share functionality with the various I/Os
needed for the peripheral units.
functions are connected to the pins in a logic AND fashion. In order to enable the
alternate function on a port pin, that pin must have a “1” in its corresponding port register bit,
otherwise the input/output will always be “0”. Furthermore, each pin must be configured
for the correct input/output mode as required by its peripheral before it may be used as such.
Table 13-4
Table 13-4.
Table 13-5.
Port Pin
P1.0
P1.1
P1.2
P1.3
P1.4
P1.5
P1.6
P1.7
P3.0
P3.1
PxM0.y
0
0
1
1
shows how to configure a generic pin for use with an alternate function.
Alternate Function Configurations for Pin y of Port x
Port Pin Alternate Functions
PxM0.y
P1M0.0
P1M0.1
P1M0.2
P1M0.3
P1M0.4
P1M0.5
P1M0.6
P1M0.7
P3M0.0
P3M0.1
Configuration Bits
PxM1.y
0
1
0
1
Table 13-5
PxM1.y
P1M1.0
P1M1.1
P1M1.2
P1M1.3
P1M1.4
P1M1.5
P1M1.6
P1M1.7
P3M1.0
P3M1.1
lists the alternate functions of the port pins. Alternate
Px.y
Alternate
Function
X
1
1
1
MOSI
MISO
GPI0
GPI1
GPI2
GPI3
GPI4
GPI5
GPI6
GPI7
AIN0
AIN1
RXD
SCK
TXD
SS
Notes
input-only
input-only
Resets to quasi-bidirectional
I/O Mode
bidirectional (internal pull-up)
output
input
bidirectional (external pull-up)
RST must be disabled
OH
while the device is
3621E–MICRO–11/10