P89LPC9402FBD,557 NXP Semiconductors, P89LPC9402FBD,557 Datasheet - Page 29

• Manufacturer Part Number: P89LPC9402FBD,557
• Description: IC 80C51 MCU FLASH 8K 64-LQFP
• Manufacturer: NXP Semiconductors
• Series: LPC900r

Specifications of P89LPC9402FBD,557

• Program Memory Type: FLASH
• Program Memory Size: 8KB (8K x 8)
• Package / Case: 64-LQFP
• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 18MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, LED, POR, PWM, WDT
• Number Of I /o: 23
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 2.4 V ~ 3.6 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: P89LPC
• Core: 80C51
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: I2C, SPI, UART
• Maximum Clock Frequency: 18 MHz
• Number Of Programmable I/os: 20
• Number Of Timers: 2
• Operating Supply Voltage: 2.4 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 935288631557

NXP Semiconductors
P89LPC9402_1
Product data sheet
7.20.10 The 9
7.20.7 Break detect
7.20.8 Double buffering
7.20.9 Transmit interrupts with double buffering enabled (modes 1, 2 and 3)
Break detect is reported in the status register (SSTAT). A break is detected when
11 consecutive bits are sensed LOW. The break detect can be used to reset the device
and force the device into ISP mode.
The UART has a transmit double buffer that allows buffering of the next character to be
written to SBUF while the first character is being transmitted. Double buffering allows
transmission of a string of characters with only one stop bit between any two characters,
as long as the next character is written between the start bit and the stop bit of the
previous character.
Double buffering can be disabled. If disabled (DBMOD, i.e., SSTAT.7 = 0), the UART is
compatible with the conventional 80C51 UART. If enabled, the UART allows writing to
SnBUF while the previous data is being shifted out. Double buffering is only allowed in
Modes 1, 2 and 3. When operated in Mode 0, double buffering must be disabled
(DBMOD = 0).
Unlike the conventional UART, in double buffering mode, the TX interrupt is generated
when the double buffer is ready to receive new data.
If double buffering is disabled TB8 can be written before or after SBUF is written, as long
as TB8 is updated some time before that bit is shifted out. TB8 must not be changed until
the bit is shifted out, as indicated by the TX interrupt.
If double buffering is enabled, TB8 must be updated before SBUF is written, as TB8 will
be double-buffered together with SBUF data.
th
bit (bit 8) in double buffering (modes 1, 2 and 3)
Rev. 01 — 22 April 2009
8-bit microcontroller with accelerated two-clock 80C51 core
P89LPC9402
© NXP B.V. 2009. All rights reserved.
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