Universal Serial Bus (USB)
18-32
Am186™CC/CH/CU Microcontrollers User’s Manual
18.5.12.3
Data Endpoint Definition
The Am186CC and Am186CU microcontrollers each provide four general-purpose data
endpoints. These endpoints transfer large amounts of data between the USB host and
device using either the USB bulk, isochronous, or interrupt transfer protocols. Note that if
the data endpoint is programmed for interrupt transfer, the DMA mode is not applicable.
Typically, all of the USB Device Class specifications require that a USB device contain any
number and type of data endpoints to transfer the various data types required by the device
class.
The data endpoint features are highly programmable. Device software can modify these
features at any time in response to the various commands issued to the device’s control
endpoint. Table 18-9 lists the data endpoint features.
Table 18-9
Data Endpoints A–D Definition
Parameter
Values
USB Parameters
Number
1–15
Configuration
0–3
Interface
0–3
Alternate Setting
0–7
Direction
(Endpoints A and C)
IN or OUT
OUT
Direction
(Endpoints B and D)
IN
Type
Interrupt,
Bulk, or
Isochronous
Bulk
Isochronous
Bulk
Isochronous
Max. Packet Size
(Endpoints A and B)
1–16 bytes
(8 or 16 for
bulk)
8, 16, 32, or
64 bytes
1–1023
bytes
1
Notes:
1. A 24-MHz processor clock is not fast enough for software to keep up with 1023-byte isochronous
IN or OUT packets using only an 8, 16, or 32-byte FIFO. If a 24-MHz processor clock is used and a
Max Packet Size of 1023 bytes is required for isochronous data, use endpoint C or D and set the
FIFO size to 64 bytes.
8, 16, 32, or
64 bytes
1–1023
bytes
1
Max. Packet Size
(Endpoints C and D)
1–64 bytes
(8 16, 32, or
64 for bulk)
8, 16, 32, or
64 bytes
1–1023
bytes
8, 16, 32, or
64 bytes
1–1023
bytes
System Parameters
Data Handling
Polled I/O
or Interrupt
Driven
General-Purpose DMA
SmartDMA Channel
FIFO Depth
(Endpoints A and B)
8 or 16 bytes
FIFO Depth
(Endpoints C and D)
8, 16, 32, or 64 bytes
Содержание Am186 CC
Страница 1: ...Am186 CC CH CU Microcontrollers User s Manual Order 21914B...
Страница 4: ...iv Am186 CC CH CU Microcontrollers User s Manual...
Страница 18: ...Table of Contents xviii Am186 CC CH CU Microcontrollers User s Manual...
Страница 24: ...Introduction xxiv Am186 CC CH CU Microcontrollers User s Manual...
Страница 39: ...Architectural Overview Am186 CC CH CU Microcontrollers User s Manual 1 15 Figure 1 6 32 Channel Linecard CH CC...
Страница 40: ...Architectural Overview 1 16 Am186 CC CH CU Microcontrollers User s Manual...
Страница 86: ...System Overview 3 36 Am186 CC CH CU Microcontrollers User s Manual...
Страница 92: ...Emulator Support 4 6 Am186 CC CH CU Microcontrollers User s Manual...
Страница 112: ...DRAM Controller 6 8 Am186 CC CH CU Microcontrollers User s Manual...
Страница 134: ...Interrupts 7 22 Am186 CC CH CU Microcontrollers User s Manual...
Страница 186: ...Programmable I O Signals 9 8 Am186 CC CH CU Microcontrollers User s Manual...
Страница 200: ...Watchdog Timer 11 6 Am186 CC CH CU Microcontrollers User s Manual...
Страница 232: ...Asynchronous Serial Ports UARTs 13 24 Am186 CC CH CU Microcontrollers User s Manual...
Страница 242: ...Synchronous Serial Port SSI 14 10 Am186 CC CH CU Microcontrollers User s Manual...
Страница 264: ...High Level Data Link Control HDLC 15 22 Am186 CC CH CU Microcontrollers User s Manual...
Страница 332: ...Universal Serial Bus USB 18 34 Am186 CC CH CU Microcontrollers User s Manual...
Страница 348: ...Register Summary A 16 Am186 CC CH CU Microcontrollers User s Manual...
Страница 376: ...Index Index 18 Am186 CC CH CU Microcontrollers User s Manual...