AT89C51SND2C-7FTUL Atmel, AT89C51SND2C-7FTUL Datasheet - Page 177

• Manufacturer Part Number: AT89C51SND2C-7FTUL
• Description: IC 8051 MCU FLASH 64K MP3 100BGA
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C51SND2C-7FTUL

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, IDE/ATAPI, MMC, SPI, UART/USART, USB
• Peripherals: Audio, I²S, MP3, PCM, POR, WDT
• Number Of I /o: 32
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Ram Size: 2.25K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.3 V
• Data Converters: A/D 2x10b; D/A 2x20b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-TFBGA
• Data Bus Width: 8 bit
• Data Ram Size: 2.25 KB
• Interface Type: ATAPI, I2S, IDE, SPI, UART, USB
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 2
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: AT89C51SND2C7FTUL

20.7
4341H–MP3–10/07
Interrupt
The Serial I/O Port handles 2 interrupt sources that are the “end of reception” (RI in SCON) and
“end of transmission” (TI in SCON) flags. As shown in Figure 20-16 these flags are combined
together to appear as a single interrupt source for the C51 core. Flags must be cleared by soft-
ware when executing the serial interrupt service routine.
The serial interrupt is enabled by setting ES bit in IEN0 register. This assumes interrupts are glo-
bally enabled by setting EA bit in IEN0 register.
Depending on the selected mode and weather the framing error detection is enabled or dis-
abled, RI flag is set during the stop bit or during the ninth bit as detailed in Figure 20-17.
Figure 20-16. Serial I/O Interrupt System
Figure 20-17. Interrupt Waveforms
SMOD0 = X
SMOD0 = 1
SMOD0 = 0
SMOD0 = 1
SMOD0 = 1
RXD
RXD
FE
FE
RI
RI
RI
Start Bit
Start bit
SCON.0
SCON.1
RI
TI
D0
D0
D1
D1
D2
b. Mode 2 and 3
D2
IEN0.4
a. Mode 1
ES
D3
D3
8-bit Data
AT8xC51SND2C/MP3B
9-bit data
D4
D4
Serial I/O
Interrupt Request
D5
D5
D6
D6
D7
D7
Stop Bit
D8
Stop bit
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