AT91SAM7S256D-AU Atmel, AT91SAM7S256D-AU Datasheet - Page 276

• Manufacturer Part Number: AT91SAM7S256D-AU
• Description: ARM Microcontrollers - MCU 256K Flash SRAM 64K ARM based MCU
• Manufacturer: Atmel
• Series: SAM7S256r

Specifications of AT91SAM7S256D-AU

• Rohs: yes
• Core: ARM
• Processor Series: AT91SAM
• Data Bus Width: 16 bit/32 bit
• Maximum Clock Frequency: 55 MHz
• Program Memory Size: 256 KB
• Data Ram Size: 64 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 3 V to 3.6 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: LQFP-64
• Mounting Style: SMD/SMT
• Interface Type: 2-Wire, I2S, SPI, USART
• Length: 7 mm

28.6.3.2
Figure 28-6. Master Mode Flow Diagram S
28.6.3.3
The SPI Baud rate clock is generated by dividing the Master Clock (MCK), by a value between 1 and 255.
Master Mode Flow Diagram
Clock Generation
1
SPI_RDR(RD) = Serializer
Serializer = SPI_TDR(TD)
NPCS = SPI_TDR(PCS)
Delay DLYBCT
Delay DLYBCS
Delay DLYBS
Data Transfer
NPCS = 0xF
SPI Enable
TDRE = 1
RDRF = 1
CSAAT ?
CSAAT ?
TDRE ?
TDRE ?
0
0
1
0
PS ?
1
peripheral
Variable
0
1
1
0
NPCS = SPI_MR(PCS)
peripheral
Fixed
NPCS = SPI_TDR(PCS)
- NPCS defines the current Chip Select
- CSAAT, DLYBS, DLYBCT refer to the fields of the
- When NPCS is 0xF, CSAAT is 0.
Chip Select Register corresponding to the Current Chip Select
SPI_TDR(PCS)
Delay DLYBCS
NPCS = 0xF
= NPCS ?
no
1
PS ?
peripheral
Variable
0
SAM7S Series [DATASHEET]
yes
peripheral
Fixed
NPCS = SPI_MR(PCS),
Delay DLYBCS
SPI_MR(PCS)
NPCS = 0xF
= NPCS ?
no
SPI_TDR(PCS)
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