5.3
EZ-USB Core Response to EP0 Device Requests
Table 5-2 shows how the EZ-USB core responds to endpoint zero requests when
ReNum=0.
Table 5-2. How the EZ-USB Core Handles EP0 Requests When ReNum=0
bRequest
0x00
0x00
0x00
0x01
0x01
0x02
0x03
0x03
0x04
0x05
0x06
0x07
0x08
0x09
0x0A
0x0B
0x0C
Name
Action: ReNum=0
Returns two zero bytes
Get Status/Device
Get Status/Endpoint
Get Status/Interface
Clear Feature/Device
Supplies EP Stall bit for indicated EP
Returns two zero bytes
None
Clear Feature/Endpoint Clears Stall bit for indicated EP
(reserved)
None
Set Feature/Device
Set Feature Endpoint
(reserved)
None
Sets Stall bit for indicated EP
None
Set Address
Updates FNADD register
Supplies internal table
None
Get Descriptor
Set Descriptor
Get Configuration
Set Configuration
Get Interface
Returns internal value
Sets internal value
Returns internal value (0-3)
Sets internal value (0-3)
None
Set Interface
Sync Frame
Vendor Requests
0x0A
Firmware Load
Upload/Download RAM
Reserved by Cypress Semiconductor
None
0xA1-0xAF Reserved
all other
The USB host enumerates by issuing:
•
•
•
Set_Address
Get_Descriptor
Set_Configuration (to 1)
Page 5-4
Chapter 5. EZ-USB CPU
EZ-USB TRM v1.9