AN2131QC Cypress Semiconductor Corp, AN2131QC Datasheet - Page 129

• 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

As Figure 7-4 illustrates, the 8051 responds to the SUDAV interrupt by decoding the eight
bytes the EZ-USB core has copied into RAM at SETUPDAT. The 8051 answers a
Get_Status request (bRequest=0) by loading two bytes into the IN0BUF buffer and load-
ing the byte count register IN0BC with the value “2.” The EZ-USB core transmits these
two bytes in response to an IN token. Finally, the 8051 clears the HSNAK bit (by writing
“1” to it) to instruct the EZ-USB core to ACK the status stage of the transfer.
The following tables show the eight SETUP bytes for Get_Status requests.
Get_Status-Device queries the state of two bits, Remote Wakeup and Self-Powered. The
Remote Wakeup bit indicates whether or not the device is currently enabled to request
remote wakeup. Remote wakeup is explained in Chapter 11, "EZ-USB Power Manage-
ment." The Self-Powered bit indicates whether or not the device is self-powered (as
opposed to USB bus-powered).
The 8051 returns these two bits by loading two bytes into IN0BUF, and then loading a
byte count of two into IN0BC.
Page 7-8
Byte
Byte
0
1
2
3
4
5
6
7
0
1
2
3
4
5
6
7
Table 7-3. Get Status-Device (Remote Wakeup and Self-Powered Bits)
bmRequestType
bRequest
wValueL
wValueH
wIndexL
wIndexH
wLengthL
wLengthH
bmRequestType
bRequest
wValueL
wValueH
wIndexL
wIndexH
wLengthL
wLengthH
Field
Field
Table 7-4. Get Status-Endpoint (Stall Bits)
Value
Value
0x80
0x00
0x02
0x00
0x82
0x00
0x02
0x00
0x00
0x00
0x00
0x00
0x00
0x00
0x00
EP
Chapter 7. EZ-USB CPU
IN, Device
“Get Status”
Two bytes requested
IN, Endpoint
“Get Status”
Endpoint Number
Two bytes requested 0x80-0x87: IN0-IN7
Meaning
Meaning
Load two bytes into IN0BUF
Byte 0 : bit 0 = Self Powered bit
Byte 1 : zero
Load two bytes into IN0BUF
Byte 0 : bit 0 = Stall bit for EP(n)
Byte 1 : zero
EP(n):
0x00-0x07: OUT0-OUT7
: bit 1 = Remote Wakeup
8051 Response
8051 Response
EZ-USB TRM v1.9