M55800A Atmel Corporation, M55800A Datasheet - Page 141

• Manufacturer Part Number: M55800A
• Manufacturer: Atmel Corporation

Specifications of M55800A

• Flash (kbytes): 0 Kbytes
• Pin Count: 176
• Max. Operating Frequency: 33 MHz
• Cpu: ARM7TDMI
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 58
• Ext Interrupts: 58
• Usb Speed: No
• Usb Interface: No
• Spi: 1
• Uart: 3
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 72
• Resistive Touch Screen: No
• Dac Channels: 1
• Dac Resolution (bits): 10
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 8
• Self Program Memory: NO
• External Bus Interface: 1
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 3.3/5.0
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 6
• Output Compare Channels: 6
• Input Capture Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: No

18.6.2
1745F–ATARM–06-Sep-07
Receive Break
The standard break transmission sequence is:
1. Wait for the transmitter ready
2. Send the STTBRK command
3. Wait for the transmitter ready
4. Send the STPBRK command
The next byte can then be sent:
5. Wait for the transmitter ready
6. Send the next byte
Each of these steps can be scheduled by using the interrupt if the bit TXRDY in US_IMR is set.
For character transmission, the USART channel must be enabled before sending a break.
The receiver detects a break condition when all data, parity and stop bits are low. When the low
stop bit is detected, the receiver asserts the RXBRK bit in US_CSR. An end of receive break is
detected by a high level for at least 1-bit + 1/16 of a bit period in asynchronous operating mode
or at least one sample in synchronous operating mode. RXBRK is also asserted when an end of
break is detected.
Both the beginning and the end of a break can be detected by interrupt if the bit
US_IMR.RXBRK is set.
(US_CSR.TXRDY = 1)
(write 0x0200 to US_CR)
(bit TXRDY = 1 in US_CSR)
(write 0x0400 to US_CR)
(bit TXRDY = 1 in US_CSR)
(write byte to US_THR)
AT91M5880A
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