AN2131QC Cypress Semiconductor Corp, AN2131QC Datasheet - Page 234

• 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

Bit 2-0:
The 8051 sets these bits to select an endpoint prior to setting its R or S bit. Valid values
are 0-7 to correspond to bulk endpoints IN0-IN7 and OUT0-OUT7.
Every millisecond the host sends a SOF token indicating “Start Of Frame,” along with an
11-bit incrementing frame count. The EZ-USB copies the frame count into these registers
at every SOF. One use of the frame count is to respond to the USB SYNC_FRAME
request (Chapter 7, "EZ-USB Endpoint Zero").
If the USB core detects a missing or garbled SOF, it generates an internal SOF and incre-
ments USBFRAMEL-USBRAMEH.
EZ-USB TRM v1.9
USBFRAMEL
USBFRAMEH
FC7
b7
b7
R
R
x
0
x
EP
FC6
b6
b6
R
R
0
x
x
Figure 12-33. USB Frame Count High/Low Registers
FC5
b5
b5
R
R
x
0
x
Select endpoint
USB Frame Count High
USB Frame Count Low
Chapter 12. EZ-USB Registers
FC4
b4
b4
R
R
x
0
x
FC3
b3
b3
R
0
R
x
x
FC10
FC2
b2
b2
R
R
x
x
FC1
FC9
b1
b1
R
R
x
x
Page 12-41
FC0
FC8
b0
b0
R
R
7FD8
x
7FD9
x