AN2135SC Cypress Semiconductor Corp, AN2135SC Datasheet - Page 77

• Manufacturer Part Number: AN2135SC
• Description: IC MCU 8051 8K RAM 24MHZ 44QFP
• Manufacturer: Cypress Semiconductor Corp
• Series: EZ-USB®r

Specifications of AN2135SC

• 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: 8
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 44-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1308

The Default USB Device consists of a single USB configuration containing one interface
(interface 0) with three alternate settings 0, 1, and 2. The endpoints reported for this
device are shown in Table 5-1. Note that alternate setting zero uses no interrupt or isoch-
ronous bandwidth, as recommended by the USB Specification.
Page 5-2
Another Use for the Default USB Device
The Default USB Device is established at power-on to set up a USB device capable of
downloading firmware into EZ-USB RAM. Another useful feature of the EZ-USB
default device is that 8051 code can be written to support the already-configured Generic
USB device. Before bringing the 8051 out of reset, the EZ-USB core enables certain
endpoints and reports them to the host via descriptors. By utilizing the USB default
machine (by keeping ReNum=0), the 8051 can, with very little code, perform meaningful
USB transfers that use these default endpoints. This accelerates the USB learning curve.
To see an example of how little code is actually necessary, take a look at Section 6.11,
"Polled Bulk Transfer Example."
5.2
The Default USB Device
Endpoint
10 OUT
2-OUT
4-OUT
6-OUT
8-OUT
9-OUT
10-IN
1-IN
2-IN
4-IN
6-IN
8-IN
9-IN
0
Table 5-1. EZ-USB Default Endpoints
BULK
BULK
BULK
BULK
BULK
BULK
Type
Chapter 5. EZ-USB CPU
CTL
INT
ISO
ISO
ISO
ISO
ISO
ISO
Maximum Packet Size (Bytes)
64
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Alternate Setting
64
16
64
64
64
64
64
64
16
16
16
16
16
16
1
256
256
64
64
64
64
64
64
64
64
16
16
16
16
2
EZ-USB TRM v1.9