AT90USB162 Atmel Corporation, AT90USB162 Datasheet - Page 164

• Manufacturer Part Number: AT90USB162
• Manufacturer: Atmel Corporation

Specifications of AT90USB162

• Flash (kbytes): 16 Kbytes
• Pin Count: 32
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 22
• Ext Interrupts: 21
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 2
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 0.5
• Eeprom (bytes): 512
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 2
• Output Compare Channels: 5
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

17.9.2
164
AT90USB82/162
Transmission Flow Control
stop sending characters. RTS usage and so associated flow control is enabled using RTSEN bit
in UCSRnD.
Figure 17-8. shows a reception example.
Figure 17-8. Reception Flow Control Waveform Example
Figure 17-9. RTS behavior
RTS will rise at 2/3 of the last received stop bit if the receive fifo is full.
To ensure reliable transmissions, even after a RTS rise, an extra-data can still be received and
stored in the Receive Shift Register.
The transmission flow can be controlled by hardware using the CTS pin controlled by the exter-
nal receiver. The aim of the flow control is to stop transmission when the receiver is full of data
(CTS = 1). CTS usage and so associated flow control is enabled using CTSEN bit in UCSRnD.
The CTS pin is sampled at each CPU write and at the middle of the last stop bit that is
curently being sent.
Figure 17-10. CTS behavior
Read from CPU
Write from CPU
RXD
RTS
TXD
CTS
sample
Start
Start
Index
FIFO
RXD
RTS
Byte0
Byte0
Stop
Stop
0
sample
C1 C2
1
Start
Start
2
CPU Read
1
Byte1
Byte1
C3
0
Stop
Stop
1
sample
1 additional byte may be sent
if the transmitter misses the RTS trig
7707F–AVR–11/10
Start
Start
Byte2
Byte2