[EZ-USB FX3] Added descriptor in USB 2.0

在 USB descriptor 的規格中, 定義了從 device/configuration/interface/endpoint, 從上而下的樹狀結構. 一個 device 可以有數個 configurtion, 一個 configuration 可以有數個 interface, 一個 interface 可以有數個 endpoint, 可以很清楚的瞭解到 device 提供了那些互動的方式.
當功能和 interface 是 1:1 對應的時候, 這些看來都沒有問題.

然而, 如果一個 device 如果有一個功能, 用到不同的 interface, 這樣主機端就不能由原先 device 傳回來的 descriptor, 看出這兩個 interface 是屬於同一組 (也許驅動程式根本就是同一個).

Interface Association Descriptors

因此, 在 USB 2.0 的規格推出後, 又以 ECN (Engineering Change Note) 的形式, 提出一個新的 descriptor, 在 USB 3.0 這是規格的一部份. 這一個 descriptor 就是在描述 interface 彼此之間的關係.

Offset	Field	Size	Value	Description
0	bLength	1	Number	Size of Descriptor in bytes	0x09
1	bDescriptorType	1	Constant	Interface Association Descriptor	0x0B
2	bFirstInterface	1	Number	Interface number of the first interface that is associated with this function
3	bInterfaceCount	1	Number	Number of contiguous interfaces that at associated with this function
4	bFunctionClass	1	Class	Class Code (assigned by USB-IF)
5	bFunctionSubClass	1	SubClass	Sub Class Code (asigned by USB-IF)
6	bFunctionProtocol	1	Protocol	Protocol Code (assigned by USB-IF)
7	iFunction	1	Index	Index of string descriptor describing this function

[EZ-USB FX3] USB 3.0 Additional Descriptors

SuperSpeed USB 3.0 增加兩個新的 descriptors, 用來儲存 technology 及 device function 的特定資訊.

Binary device Object Store (BOS)

BOS descriptor 作為一個或是更多的 device capability descriptor 的基礎的 descriptor, 提供特定的能力和技術的資訊.
所有的 SuperSpeed USB 3.0 設備都必需支援這一個 descriptor, 並且在 high speed 運行時, 支援 Link Power Management (LPM).

Offset	Field	Size	Value	Description
0	bLength	1	Number	Size of Descriptor in bytes	0x05
1	bDescriptorType	1	Constant	BOS Descriptor	0x0F
2	wTotalLength	2	Number	The number of bytes in this descriptor and all of its subordinate descriptors	include all sub desceiptors
4	bNumDeviceCaps	1	Number	The number of device capability descriptors subordinate to this BOS descriptor.

Device Capability Descriptor

Device Capability Descriptor 描述各不同 Device 的 capability

Offset	Field	Size	Value	Description
0	bLength	1	Number	Size of Descriptor in bytes
1	bDescriptorType	1	Constant	DevCapability Descriptor	0x10
2	bDevCapabilityType	1	Number	Device Capability Type
3	Capability-Dependent	Var	Variable	Capability-specific data and format

 

Device Capability Types Codes

Capability Code	Value	Descriptor
Wireless_USB	01H	Defines the set of Wireless USB-specific device level capabilities
USB 2.0 Extension	02H	USB 2.0 Extension Descriptor
SUPERSPEED_USB	03H	Defines the set of SuperSpeed USB specific device level capabilities
CONTAINER_ID	04H	Defines the instance unique ID used to identify the instance across all operating modes
PLATFORM	05H	Defines a device capability specific to a particular platform/operating system
POWER_DELIVERY_CAPABILITY	06H	Defines the various PD Capabilities of this device
BATTERY_INFO_CAPABILITY	07H	Provides information on each battery supported by the device
PD_CONSUMER_PORT_CAPABILITY	08H	The consumer characteristics of a port on the device
PD_PROVIDER_PORT_CAPABILITY	09H	The provider characteristics of a port on the device
SUPERSPEED_PLUS	0AH	Defines the set of SuperSpeed Plus USB specific device level capabilities
PRECISION_TIME_MEASUREMENT	0BH	Precision Time Measurement (PTM) Capability Descriptor
Wireless_USB_Ext	0CH	Defines the set of Wireless USB 1.1-specific device level capabilities
Reserved	00H, 0DH~FFH	Reserved for future use

[EZ-USB FX3] Notes on USB 2.0 descriptors

USB 的 descriptor 是 host 識別 device 的資料. 當一個 USB 的設備插入 USB port 時, USB host 會主動詢問 USB 設備的相關資料, 以載入相對應的驅動程式, 以及供給電源等動作. USB 設備就是透過 USB descriptor 來傳達這些資訊.
USB descriptor 的結構如附圖. 由一個 Device Descriptor, 包含數個 Configuration Descriptor, 每一個 Configurtion Descriptor 又可以包含數個 Interface Descriptor, 每一個 Interface Descriptor 又可以包含數個 Endpoint Descriptor, 字串的部份則放在 String Descriptor 中.

Device Descriptor

USB device 只能有一個 device descriptor, 這個 descriptor 提供設備為主的資訊. 譬如說對應到 USB 的規格的版本, 設備供應商的代號, 產品代號, 等等.

Offset	Field	Size	Value	Description	Note
0	bLength	1	Number	size of the descriptor in bytes	0x12
1	bDescriptorType	1	Constant	DeviceDescriptor (0x01)	0x01
2	bcdUSB	2	BCD	USB Sepcification Number	USB 3.0 0x00, 0x03 USB 2.1 0x10, 0x02
4	bDeviceClass	1	Class	Class Code: 0x00: each interface specifies it’s own claas code 0xFF: the class code is vendor specified Otherwise:	0xEF Miscellaneous
5	bDeviceSubClass	1	SubClass	Assigned by USB ORG	0x02
6	bDeviceProtocol	1	Protocol	Assigned by USB ORG	0x01
7	bMaxPacketSize	1	Number	Maximum Packet Size for Endpoint 0	8/16/32/64
8	idVendor	2	ID	Assigned by USB ORG
10	idProduct	2	ID	Assigned by Manufacturer
12	bcdDevice	2	BCD	Device Release Number
14	iManufacturer	1	Index	Index of Manufacturer String Descriptor
15	iProduct	1	Index	Index of Product String Descriptor
16	iSerialNumber	1	Index	Index of Serial Number String Descriptor
17	bNumConfigurations	1	Integer	Number of Possible Configurations

Class/SubClass/Protocol 共同指定了 USB device 的類型. 譬如說, Class = 0xEF, SubClass = 0x02, Protocol = 0x01, 指定了這個 device 是一個 Miscelaneous device ( Class = 0xEF), SubClass = 0x02, Protocol = 0x01, 則說明這個 device 的 Class Code, 是由 Interface Association Descriptor 指定. 也就是需參照 Interface Descriptor.

Configuration Descriptor

Configuration Descriptor 指定裝置在這個 configuration 的狀態下的電力設定及所需要的電力供應. 通常一個設備只會用到一個 configuration, 但是如果設備可以支援自我供電以及 USB 供電兩種方式的時候, 可以有兩個以上的 configuration, 以供 host 選擇, 但是同一時間只能有一個作用中的 configurtion.
舉例來說, 可以有一個高功率需求的 bus 供電 configuration, 以及一個自我供電的 configuration. 如果 USB device 被插入一個有電源供應的系統, 驅動程式可以選擇 bus 供電. 如果是被插入沒有電源供給的系統 (以系統的電池供電), 則可以選擇設備自我供電.

Offset	Field	Size	Value	Description
0	bLength	1	Number	Size of Descriptor in bytes	0x09
1	bDescriptorType	1	Constant	Configuration Descriptor	0x02
2	wTotalLength	2	Number	Total Length of Data returned	include all sub desceiptors
4	bNumInterfaces	1	Number	Number of Interfaces	number of interface in this configuration
5	bConfigurationValue	1	Number	Value to use as an argument to select this configuration	Configuration value to be selected
6	iConfiguration	1	Index	Index of String Descriptor Describing this configuration
7	bmAttributes	1	Bitmap	D7: Bus Powered D6: Self Powered D5: Remote Wakeup D4..D0 reserved (0)
8	bMaxPower	1	mA	Maximum Power Consumption

 

Interface Descriptor

interface descriptor 可以看成是一組 endpoints 所組成的功能群組, 以達成特定功能. 例如, 一個多功能事務機, 可以用一個 interface descriptor 來描述 fax 功能的 endpoints, 然後用另一個 interface descriptor 來描述 scanner, 再一個來描述 printer. 和 configuration descriptor 不同的是, interface descriptor 沒有在同一時間內只能有一個在運作中的限制. USB 設備可以有一個或更多的 interface 在運作中.
interface descriptors 有一個 bInterfaceNumber 的欄位, 用以指定這一個 interface. 另外, 還有一個 bAlternateSetting 欄位, 這可以讓 interface 達成動態變更的效果.
假設, 我們有一個設備, 它有兩個 interface, interface 1, interface 2. interface 1 的 bInterfaceNumber 設成 0, 表示它是第一個 interface descriptor, 並且 bAlternativeSetting 設成 0. interface 2 的 bInterfaceNumber 設成 1, 表示它是第二個 interface descriptor, 並且 bAlternativeSetting 設成 0. 當我們可以再加入一個 interface descriptor, 並且把 bInterfaceNumber 設成 1, 表示它也是第二個 interface descriptor, 但是這次把 bAlternativeSetting 設定為 1, 表示這一個 interface descriptor 是另一個 interface descriptor 的替代.

Offset	Field	Size	Value	Description
0	bLength	1	Number	Size of Descriptor in bytes	0x09
1	bDescriptorType	1	Constant	Interface Descriptor	0x04
2	bInterefaceNumber	1	Number	Number of Interface	zero based interface descriptor
3	bAlternateSetting	1	Number	Value used to select alternative setting	0: Not alternative 1: alternative
4	bNumEndpoints	1	Number	Number of Endpoints used for this interface
5	bInterfaceClass	1	Class	Assigned by USB ORG
6	bInterfaceSubClass	1	SubClass	Assigned by USB ORG
7	bInterfaceProtocol	1	Protocol	Protocol Code
8	iInterface	1	Index	Index of String Descriptor

 

Endpoint Descriptor

每一個 endpoint descriptor 都是用來指定傳輸的型態, 方向, 輪詢間隔, 最大的封包大小. Endpoint 0, 是預設的控制 endpoint, 只會是 control point, 所以不需要 descriptor.

Offset	Field	Size	Value	Description
0	bLength	1	Number	Size of Descriptor in bytes	0x07
1	bDescriptorType	1	Constant	End Descriptor	0x05
2	bEndpointAddress	1	Endpoint	Endpoint Address 0b..3b Endpoint NUmber 4b..6b Reserved ( Zero) 7b Direction    0 : Out Endpoint    1 : In Endpoint	zero based interface descriptor
3	bmAttributes	1	Bitmap	Bits 0..1 Transfer Type   00 = Control   01 = Isochronous   10 = Bulk   11 = Interrupt Bits 5..2 reserved if not Isochronous. Bits 3..2 Synchronization type   00 = No Synchronization   01 = Asynchronous   10 = Adaptive   11 = Synchronous Bits 5..4 Usage type   00 = Data endpoint   01 = Feedback endpoint   10 = Implicit feedback Data endpoint   11 = Reserved	0: Not alternative 1: alternative
4	wMaxPacketSize	2	Number	Maximum Packet Size .
6	bInterval	1	Number	Polling interval in frame count. Bulk & Control Endpoint ignored. Iso must equal 1 Interrupt 1..255

 

String Descriptor

string descriptor 提供可讀的資訊. 如果不提供這一個 string descriptor, string index 需要設成 0. string 以 Unicode 編碼, 並且提供多國語言的支援.
String Descriptor Zero, 是用來描述所支持的語言 :

Offset	Field	Size	Value	Description
0	bLength	1	Number	Size of Descriptor in bytes
1	bDescriptorType	1	Constant	String Descriptor	0x03
2	wLANGID[0]	2	Number	Supported Language Code Zero	ex 0x0409 (English, USA)
	wLANGID[1]	2	Number	Supported Language Code One	ex 0x0C09 (English, Austria)
4	wLANGID[2]	2	Number	Supported Language Code X	ex 0x0407 (German – Standard)

String Descriptor 1~, 是放置 Unicode 字串的地方.

Offset	Field	Size	Value	Description
0	bLength	1	Number	Size of Descriptor in bytes
1	bDescriptorType	1	Constant	String Descriptor	0x03
2	bString	n	Unicode	Supported Language Code Zero	Unicode Encoded String

 

Device Qualifier

device_qualifier descriptor 描述關於高速設備在不同速度下的訊息改變. 例如, 如果設備正在 full-speed 下運作, device_qualifier 傳回它在 high-speed 下運作的資訊. 反之亦然.

Offset	Field	Size	Value	Description
0	bLength	1	Number	Size of Descriptor in bytes
1	bDescriptorType	1	Constant	Device Qualifier Type
2	bcdUSB	2	BCD	USB spec version number.
4	bDeviceClass	1	Class	Class Code
5	bDeviceSubClass	1	SubClass	SubClass Code
6	bDeviceProtocol	1	Protocol	Protocol Code
7	bMaxPacketSize0	1	Number	Maximum packet size for other speed
8	bNumConfigurations	1	Number	Number of Other-speed configurations
9	bReserved	1	Zero	Reserved for future use, must be zero

[EZ-USB FX3] Debug with J-Link GDB

這邊主要是記錄在使用 J-Link debug 的時候, 需要進行的操作. 因為對每一個 project 都需要設定, 所以只好記錄起來.

Create Debug Configuration

1. 在左邊的 Project Explorer 中, 點選要 debug 的 project, 這個地方是 UartLpDmaMode

2. 在上面的 Run 選單中, 選擇 Debug Configurations

3. 在左邊的 configurations 中, 選擇 Zylin Embedded debug (Native)

4. 在 Zylin Embedded debug (Native) 上按右鍵, 選擇 new

 

Modify Debug Configuration

1. 選擇 Debugger 分頁, 把 Main 分頁的 GDB debugger 連結到 C:\Program Files (x86)\Cypress\EZ-USB FX3 SDK\1.3\ARM GCC\bin\arm-none-eabi-gdb.exe”


2. 選擇 Commands 分頁, 在 Initialize commands, 加入以下命令
set prompt (arm-gdb)
# This connects to a target via netsiliconLibRemote
# listening for commands on a TCP port on the local machine.
# 2331 if the Segger J-Link GDB Server is being used
# 3333 if OpenOCD is being used
# If OpenOCD is being used, the CPU should be halted
# using the "monitor halt" command.
# Uncomment the appropriate line below:
target remote localhost:2331
# target remote localhost:3333
# monitor halt
monitor speed 1000
monitor endian little
set endian little
monitor reset
# Set the processor to SVC mode
monitor reg cpsr =0xd3
# Disable all interrupts
monitor memU32 0xFFFFF014 =0xFFFFFFFF
# Enable the TCMs
monitor memU32 0x40000000 =0xE3A00015
monitor memU32 0x40000004 =0xEE090F31
monitor memU32 0x40000008 =0xE240024F
monitor memU32 0x4000000C =0xEE090F11
# Change the FX3 SYSCLK setting based on
# input clock frequency. Update with
# correct value from list below.
# Clock input is 19.2 MHz: Value = 0x00080015
# Clock input is 26.0 MHz: Value = 0x00080010
# Clock input is 38.4 MHz: Value = 0x00080115
# Clock input is 52.0 MHz: Value = 0x00080110
monitor memU32 0xE0052000 = 0x00080015
# Add a delay to let the clock stabilize.
monitor sleep 1000
set $pc =0x40000000
si
si
si
si
3. 選擇 Commands 分頁, 在 Run commands, 加入以下命令
load
按下 “Apply” 儲存設定.

Run GDB server

1. 啟動 GDB server.
在開始功能表中, 找到 SEGGER, 執行 SEGGER\J-Link V4.9X.x\J-Link GDB Server. 確認以下的設定. 沒有問題的話, 按下 OK 開始.

正常的話, 會顯示未連線.

Debug from Eclipse

在專案名稱上按右鍵, 選擇 Debug As\Debug Configurations. 確定在左邊的 debug configuration 選項中, 剛剛建立的 configuration 被選擇. 然後按下 debug.

出現切換到 debug view 的提示. Eclipse 的 source code view 及 debug view 是在歸屬在不同的視覺系統中. 所以進到 debug 時, 會切換到 debug view. 這只是提示. 按下 “Yes” 進入 debug view.
進入 debug 後, 系統會先停下來. 看起來會像是這個樣子.

按下工具列的 resume 按紐

程式會停在 main() 的第一行 , GDB server 也會顯示已連線