AT89C5122D-PSTUM Atmel, AT89C5122D-PSTUM Datasheet - Page 144

• Manufacturer Part Number: AT89C5122D-PSTUM
• Description: IC 8051 MCU FLASH 32K 64QFN
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C5122D-PSTUM

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 48MHz
• Connectivity: SmartCard, SPI, UART/USART, USB
• Peripherals: LED, POR, WDT
• Number Of I /o: 46
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-QFN
• For Use With: AT89STK-10 - KIT EVAL APPL MASS STORAGEAT89STK-03 - KIT STARTER FOR MCU AT8XC5122/23
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -

Serial Peripheral DATa Register
(SPDAT)
144
AT83R5122, AT8xC5122/23
The Serial Peripheral Data Register (Table 87) is a read/write buffer for the receive data
register. A write to SPDAT places data directly into the shift register. No transmit buffer
is available in this model.
A read of the SPDAT returns the value located in the receive buffer and not the content
of the shift register.
Table 87. Serial Peripheral Data Register - SPDAT (C5h)
Reset Value = XXXX XXXXb
Bit Number
7-0
R7
7
Mnemonic Description
R7:0
Bit
R6
6
Receive data bits
SPCON, SPSTA and SPDAT registers may be read and written at any time while
there is no on-going exchange. However, special care should be taken when
writing to them while a transmission is on-going:
Do not change SPR2, SPR1 and SPR0
Do not change CPHA and CPOL
Do not change MSTR
Clearing SPEN would immediately disable the peripheral
Writing to the SPDAT will cause an overflow
R5
5
R4
4
R3
3
R2
2
R1
1
4202F–SCR–07/2008
R0
0