AT91SAM7S128C-MU Atmel, AT91SAM7S128C-MU Datasheet - Page 631

• Manufacturer Part Number: AT91SAM7S128C-MU
• Description: IC MCU ARM7 128K FLASH 64-QFN
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM7S128C-MU

• Core Processor: ARM7
• Core Size: 16/32-Bit
• Speed: 55MHz
• Connectivity: I²C, SPI, SSC, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, DMA, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 32K x 8
• Voltage - Supply (vcc/vdd): 1.65 V ~ 1.95 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-VQFN Exposed Pad, 64-HVQFN, 64-SQFN, 64-DHVQFN
• Core: ARM7TDMI
• For Use With: AT91SAM-ICE - EMULATOR FOR AT91 ARM7/ARM9AT91SAM7S-EK - KIT EVAL FOR ARM AT91SAM7S
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: AT91SAM7S128-MU; AT91SAM7S128-MU

40.7.10
40.7.10.1
40.7.10.2
40.7.10.3
40.7.10.4
6175K–ATARM–30-Aug-10
Two-wire Interface (TWI)
TWI: Clock Divider
TWI: Software Reset
TWI: Disabling Does not Operate Correctly
TWI: NACK Status Bit Lost
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 ini-
tiate 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.
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
AT91SAM7S Series Preliminary
CKDIV
must
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