AT91SAM9G45-EKES Atmel, AT91SAM9G45-EKES Datasheet - Page 583

• Manufacturer Part Number: AT91SAM9G45-EKES
• Description: KIT EVAL FOR AT91SAM9G45
• Manufacturer: Atmel
• Series: AT91SAM Smart ARMr
• Type: MCUr

Specifications of AT91SAM9G45-EKES

• Contents: Board
• Processor To Be Evaluated: SAM9G45
• Data Bus Width: 32 bit
• Interface Type: I2C, SPI, UART
• Maximum Operating Temperature: + 50 C
• Minimum Operating Temperature: - 10 C
• Operating Supply Voltage: 1.8 V to 3.3 V
• For Use With/related Products: AT91SAM9G45
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: Q4626953

Figure 33-24. Receiver Time-out Block Diagram
6438F–ATARM–21-Jun-10
RETTO
Character
Received
STTTO
If STTTO is performed, the counter clock is stopped until a first character is received. The idle
state on RXD before the start of the frame does not provide a time-out. This prevents having to
obtain a periodic interrupt and enables a wait of the end of frame when the idle state on RXD is
detected.
If RETTO is performed, the counter starts counting down immediately from the value TO. This
enables generation of a periodic interrupt so that a user time-out can be handled, for example
when no key is pressed on a keyboard.
Figure 33-24
Table 33-11
Table 33-11. Maximum Time-out Period
• Obtain an interrupt while no character is received. This is performed by writing US_CR with
on RXD before a new character is received will not provide a time-out. This prevents having
to handle an interrupt before a character is received and allows waiting for the next idle state
on RXD after a frame is received.
the RETTO (Reload and Start Time-out) bit at 1. If RETTO is performed, the counter starts
counting down immediately from the value TO. This enables generation of a periodic interrupt
so that a user time-out can be handled, for example when no key is pressed on a keyboard.
1
D
Baud Rate
gives the maximum time-out period for some standard baud rates.
bit/sec
14400
19200
28800
33400
1 200
2 400
4 800
9 600
Clear
shows the block diagram of the Receiver Time-out feature.
600
Q
Baud Rate
Clock
Clock
16-bit Time-out
Counter
TO
Bit Time
1 667
Load
833
417
208
104
μs
69
52
35
30
16-bit
Value
0
=
AT91SAM9G45
TIMEOUT
Time-out
109 225
54 613
27 306
13 653
6 827
4 551
3 413
2 276
1 962
ms
583