SAM7SE256 Atmel Corporation, SAM7SE256 Datasheet - Page 369

• Manufacturer Part Number: SAM7SE256
• Manufacturer: Atmel Corporation

Specifications of SAM7SE256

• Flash (kbytes): 256 Kbytes
• Pin Count: 144
• Max. Operating Frequency: 48 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 88
• Ext Interrupts: 88
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Twi (i2c): 1
• Uart: 3
• Ssc: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 384
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 32
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: sdram
• Nand Interface: Yes
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8/3.3
• Operating Voltage (vcc): 3.0 to 3.6
• Fpu: No
• Mpu / Mmu: Yes / No
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

Figure 32-24. Read Access Ordered by a MASTER
Notes:
32.9.5.2
Figure 32-25. Write Access Ordered by a Master
Notes:
6222F–ATARM–14-Jan-11
EOSVACC
EOSVACC
SVREAD
SVREAD
TXRDY
SVACC
RXRDY
SVACC
NACK
1. When SVACC is low, the state of SVREAD becomes irrelevant.
2. TXRDY is reset when data has been transmitted from TWI_THR to the shift register and set when this data has been
1. When SVACC is low, the state of SVREAD becomes irrelevant.
2. RXRDY is set when data has been transmitted from the shift register to the TWI_RHR and reset when this data is read.
TWD
TWD
acknowledged or non acknowledged.
Write Operation
S
S
ADR
ADR
TWI answers with a NACK
TWI answers with a NACK
SADR does not match,
SADR does not match,
The write mode is defined as a data transmission from the master.
After a START or a REPEATED START, the decoding of the address starts. If the slave address
is decoded, SVACC is set and SVREAD indicates the direction of the transfer (SVREAD is low in
this case).
Until a STOP or REPEATED START condition is detected, TWI stores the received data in the
TWI_RHR register.
If a STOP condition or a REPEATED START + an address different from SADR is detected,
SVACC is reset.
Figure 32-25 on page 369
W
R
NA
NA
DATA
DATA
NA
NA
P/S/Sr
P/S/Sr
describes the Write operation.
Write THR
SADR
SADR
TWI answers with an ACK
TWI answers with an ACK
SADR matches,
SADR matches,
W A
R
SVREAD has to be taken into account only while SVACC is active
SVREAD has to be taken into account only while SVACC is active
A
DATA
DATA
A
A
Read RHR
SAM7SE512/256/32
ACK/NACK from the Master
A
A
DATA NA S/Sr
DATA
NA
S/Sr
Read RHR
369