AT91SAM7S321-AU Atmel, AT91SAM7S321-AU Datasheet - Page 315

• Manufacturer Part Number: AT91SAM7S321-AU
• Description: IC ARM7 MCU FLASH 32K 64LQFP
• Manufacturer: Atmel
• Series: AT91SAMr

Specifications of AT91SAM7S321-AU

• 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: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K 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-LQFP
• Processor Series: AT91SAMx
• Core: ARM7TDMI
• Data Bus Width: 32 bit
• Data Ram Size: 8 KB
• Interface Type: I2C, I2S, SPI, SSC, TWI, UART, USB
• Maximum Clock Frequency: 55 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 10 bit
• Operating Supply Voltage: 1.8 V to 3.3 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: JTRACE-ARM-2M, KSK-AT91SAM7S-PL, MDK-ARM, RL-ARM, ULINK2
• Development Tools By Supplier: AT91SAM-ICE, AT91-ISP, AT91SAM7S-EK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• Controller Family/series: AT91SAM7xxxx
• No. Of I/o's: 32
• Ram Memory Size: 8KB
• Cpu Speed: 55MHz
• No. Of Timers: 3
• Rohs Compliant: Yes
• 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: Lead free / RoHS Compliant

30.6.3.3
6175G–ATARM–22-Nov-06
Synchronous Receiver
stop bit, regardless of the field NBSTOP, so that resynchronization between the receiver and the
transmitter can occur. Moreover, as soon as the stop bit is sampled, the receiver starts looking
for a new start bit so that resynchronization can also be accomplished when the transmitter is
operating with one stop bit.
Figure 30-10
operates in asynchronous mode.
Figure 30-10. Asynchronous Start Detection
Figure 30-11. Asynchronous Character Reception
In synchronous mode (SYNC = 1), the receiver samples the RXD signal on each rising edge of
the Baud Rate Clock. If a low level is detected, it is considered as a start. All data bits, the parity
bit and the stop bits are sampled and the receiver waits for the next start bit. Synchronous mode
operations provide a high speed transfer capability.
Configuration fields and bits are the same as in asynchronous mode.
Figure 30-12
Clock (x16)
Baud Rate
Sampling
Sampling
Sampling
Baud Rate
Example: 8-bit, Parity Enabled
Detection
Clock
RXD
RXD
Start
Clock
RXD
illustrates a character reception in synchronous mode.
and
1
1
Figure 30-11
2
2
samples
3
3
16
4
4
D0
5
5
samples
16
6
6
illustrate start detection and character reception when USART
D1
7
Detection
7
Rejection
AT91SAM7S Series Preliminary
samples
Start
Start
16
8
0
D2
1
1
samples
16
2
2
3
3
D3
samples
4
4
16
5
D4
samples
6
16
7
D5
samples
8
16
9 10 11 12 13 14 15 16
D6
samples
16
D7
samples
16
Parity
Bit
samples
16
Stop
Bit
Sampling
D0
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