AN2131QC Cypress Semiconductor Corp, AN2131QC Datasheet - Page 142

• Manufacturer Part Number: AN2131QC
• Description: IC MCU 8051 8K RAM 24MHZ 80BQFP
• Manufacturer: Cypress Semiconductor Corp
• Series: EZ-USB®r

Specifications of AN2131QC

• Applications: USB Microcontroller
• Core Processor: 8051
• Program Memory Type: ROMless
• Controller Series: AN213x
• Ram Size: 8K x 8
• Interface: I²C, USB
• Number Of I /o: 24
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 80-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1307

7.3.9 Get Interface
The 8051 simply returns the alternate setting for the requested interface IF, and clears the
HSNAK bit by writing “1” to it.
7.3.10 Set Address
When a USB device is first plugged in, it responds to device address 0 until the host
assigns it a unique address using the Set_Address request. The EZ-USB core copies this
device address into the FNADDR (Function Address) register, and subsequently responds
only to requests to this address. This address is in effect until the USB device is
unplugged, the host issues a USB Reset, or the host powers down.
The FNADDR register can be read, but not written by the 8051. Whenever the EZ-USB
core ReNumerates , it automatically resets the FNADDR to zero allowing the device to
come back as new.
An 8051 program does not need to know the device address, because the EZ-USB core
automatically responds only to the host-assigned FNADDR value. The EZ-USB core
makes it readable by the 8051 for debug/diagnostic purposes.
EZ-USB TRM v1.9
Table 7-19. Get Interface (Actually, Get Alternate Setting AS for interface IF)
Byte
0
1
2
3
4
5
6
7
bmRequestType
bRequest
wValueL
wValueH
wIndexL
wIndexH
wLengthL
wLengthH
Field
Value
0x0A “Get_Interface”
0x81
0x00
0x00
0x00
IF
1
0
Chapter 7. EZ-USB CPU
IN, Device
For this interface
LenL
LenH
Meaning
Send AS for Interface IF over
OUT0BUF (1 byte)
8051 Response
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