AT89C5122D-PSTUM Atmel, AT89C5122D-PSTUM Datasheet - Page 112

• Manufacturer Part Number: AT89C5122D-PSTUM
• Description: IC 8051 MCU FLASH 32K 64QFN
• Manufacturer: Atmel
• Series: 89Cr

Specifications of AT89C5122D-PSTUM

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 48MHz
• Connectivity: SmartCard, SPI, UART/USART, USB
• Peripherals: LED, POR, WDT
• Number Of I /o: 46
• Program Memory Size: 32KB (32K x 8)
• Program Memory Type: FLASH
• Ram Size: 768 x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-QFN
• For Use With: AT89STK-10 - KIT EVAL APPL MASS STORAGEAT89STK-03 - KIT STARTER FOR MCU AT8XC5122/23
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -

Detach Simulation
112
AT83R5122, AT8xC5122/23
In order to be re-enumerated by the Host, the AT83R5122, AT8xC5122/23 has the pos-
sibility to simulate a DETACH-ATTACH of the USB bus.
The V
D+ pull-up as shown in Figure 60. This output can be put in high-impedance when the
DETACH bit is set to 1 in the USBCON register. Maintaining this output in high imped-
ance for more than 3 μs will simulate the disconnection of the device. When resetting
the DETACH bit, an ATTACH is then simulated. The USB controller should be enabled
to use this feature.
Figure 60. Example of V
Figure 61. Disconnect Timing
V
IHZ(min)
V
V
REF
SS
IL
output voltage is between 3.0V and 3.6V. This output can be connected to the
D+
D-
V
Disconnected
REF
D-
D+
Device
REF
R2
R3
Connection
R1
>= 2,5 s
1
2
3
4
USB-B Connector
D-
D+
GND
VCC
Disconnect
Detected
4202F–SCR–07/2008