SAM7S16 Atmel Corporation, SAM7S16 Datasheet - Page 696

• Manufacturer Part Number: SAM7S16
• Manufacturer: Atmel Corporation

Specifications of SAM7S16

• Flash (kbytes): 16 Kbytes
• Pin Count: 48
• Max. Operating Frequency: 55 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 21
• Ext Interrupts: 21
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Twi (i2c): 1
• Uart: 2
• 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): 4
• Self Program Memory: NO
• Dram Memory: No
• Nand Interface: No
• 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: no / no
• Timers: 3
• Output Compare Channels: 3
• Input Capture Channels: 3
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

40.15.8
40.15.8.1
40.15.8.2
40.15.8.3
40.15.8.4
40.15.8.5
40.15.9
40.15.9.1
696
SAM7S Series
Two-wire Interface (TWI)
Universal Synchronous Asynchronous Receiver Transmitter (USART)
TWI: Clock Divider
TWI: Software Reset
TWI: Disabling Does not Operate Correctly
TWI: NACK Status Bit Lost
TWI: Possible Receive Holding Register Corruption
USART: Hardware Handshake
The value of CLDIV x 2
be less than or equal to 8191⋅
None.
When a software reset is performed during a frame and when TWCK is low, it is impossible to
initiate a new transfer in READ or WRITE mode.
None.
Any transfer in progress is immediately frozen if the Control Register (TWI_CR) is written with
the bit MSDIS at 1. Furthermore, the status bits TXCOMP and TXRDY in the Status Register
(TWI_SR) are not reset.
The user must wait for the end of transfer before disabling the TWI. In addition, the interrupts
must be disabled before disabling the TWI.
During a master frame, if TWI_SR is read between the Non Acknowledge condition detection
and the TXCOMP bit rising in the TWI_SR, the NACK bit is not set.
The user must wait for the TXCOMP status bit by interrupt and must not read the TWI_SR as
long as transmission is not completed.
TXCOMP and NACK fields are set simultaneously and the NACK field is reset after the read of
the TWI_SR.
When loading the TWI_RHR, the transfer direction is ignored. The last data byte received in the
TWI_RHR is corrupted at the end of the first subsequent transmit data byte. Neither RXRDY nor
OVERRUN status bits are set if this occurs.
The user must be sure that received data is read before transmitting any new data.
The Hardware Handshake does not work at speeds higher than 750 kbauds.
None.
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
Problem Fix/Workaround
CKDIV
must be less than or equal to 8191, the value of CHDIV x 2
6175L–ATARM–28-Jul-11
CKDIV
must