AT89LP214 Atmel Corporation, AT89LP214 Datasheet - Page 13

• Manufacturer Part Number: AT89LP214
• Manufacturer: Atmel Corporation

Specifications of AT89LP214

• Flash (kbytes): 2 Kbytes
• Max. Operating Frequency: 20 MHz
• Cpu: 8051-1C
• Max I/o Pins: 12
• Spi: 1
• Uart: 1
• Sram (kbytes): 0.125
• Operating Voltage (vcc): 2.4 to 5.0
• Timers: 2
• Isp: SPI/OCD
• Watchdog: Yes

9.2
9.3
9.4
3538E–MICRO–11/10
External Clock Source
Internal RC Oscillator
System Clock Out
The external clock option disables the oscillator amplifier and allows XTAL1 to be driven directly
by the clock source as shown in
or configured to output a divided version of the system clock.
Figure 9-2.
The AT89LP213/214 has an internal RC oscillator tuned to 8.0 MHz ±1.0% at 5.0V and 25° C.
When enabled as the clock source, XTAL1 and XTAL2 may be used as P3.2 and P3.3 respec-
tively. XTAL2 may also be configured to output a divided version of the system clock. The
frequency of the oscillator may be adjusted by changing the RC Adjust Fuses.
figuration Fuses” on page
the Atmel SIgnature.
When the AT89LP213/214 is configured to use either an external clock or the internal RC oscil-
lator, a divided version of the system clock may be output on XTAL2 (P3.3). The Clock Out
feature is enabled by setting the COE bit in CLKREG. The two CDV bits determine the clock
divide ratio. For example, setting COE = “1” and CDIV = “00” when using the internal oscillator
will result in a 4.0 MHz clock output on P3.3. P3.3 must be configured as an output in order to
use the clock out feature.
External Clock Drive Configuration
72). A copy of the initial factory setting is stored at location 0007h of
OSCILLATOR
NC, GPIO, or
EXTERNAL
Figure
CLKOUT
SIGNAL
9-2. XTAL2 may be left unconnected, used as P3.3 I/O,
XTAL2 (P3.3)
XTAL1 (P3.2)
GND
AT89LP213/214
(See “User Con-
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