The BC 1.2. 1
1.1 charger type probe
1) DCD: There 150mV (= 10uA x 15K ohm pull-down resistor) voltage on the DP, DM upper voltage 0
2) Primary Det (DP detection initiating DM):
- loading on the DP 0.6V voltage, the voltage is 0 DM, the charger type is the SDP
- 0.6V voltage on the load DP, DM upper voltage of 0.6V, Det entering Secondary
. 3) Secondary Det (DM detection initiating the DP):
- load voltage 0.8V DM, voltage of 0 on the DP, the type of charger is the CDP
- 0.8V voltage loaded on the DM, the voltage of 0.8V DP, is DCP type charger
NOTE: VDAT_REF = 0.6V, the reference voltage data line
VLGC = 0.8V, the logic voltage
Figure 1-1 CDP detected waveform
1.2 USB 2.0 ULPI PHY
Qualcomm platform 2.0 USB PHY block diagram is shown in Figure 1-2.
Figure 1-2 USB 2.0 PHY
Qualcomm platform USB 2.0 interface using ULPI since a PHY interface, the detection of the register BC 1.2 ULPI register space into a standard ULPI register space address range 0x00-0x2f, which are well gauge part (chip manufacturing address offset allowed change List), whereby the high-pass address register charger probe placed well outside of these registers address the regulations.
1.3 USB 3.0 UTMI and PIPE PHY
Qualcomm 3.0 internet USB PHY block diagram as shown in Figure 1-3.
Figure 1-3 USB 3.0 dual-bus architecture
Since USB 3.0 is a dual bus architecture, comprising both a USB 2.0 cable also contains the data lines of USB 3.0, USB 3.0 so that the physical layer is to have two parts. USB 3.0 high-pass MSM8974 of the LS / FS / HS is UTMI physical layer interfaces, SS PIPE3 with an interface (see phy-interface-pci-express- sata3-usb30-archectures.pdf), and two PHY interfaces is no built-in register, and therefore the high-pass register BC charging probe placed 1.2 AHB address space (see Figure). UTMI PHY recognition principle mainly through the control register, PIPE3 PHY interfaces do charger is not recognized.
Q & A 2
Q: role 47K resistor USB_VBUS pin?
A: the voltage on USB_VBUS rapid charging and discharging, thereby identifying a case where the external power supply has been pulled away, fast turn-off transistor, avoiding abnormal current backflow.
Abbreviations 3
ARC: Argonant RISC Core
AT91SAM9260: SAM means Smart ARM-based Microcontroller
ATMEL SAMBA: ATMEL Smart ARM-based Microcontroller the Boot Assistant
CC2530: TI ChipCon2530
DCD: the Data Business Card Detect
DWC2: the Controller Design Ware 2, the Apple embedded devices, including DWC2 iPad and iPhone are used
ISP1161: Philips' Integrated Host Solution Pairs 1161, "Firms introduce the USB Host the Controllers", HTTPS: //www.eetimes.com/document.asp doc_id = 1,290,054?
Quirks: the Attributes of A Device at The Considered to BE that are noncompliant with expected Operation
SL811HS: Cypress / ScanLogic the Host 811 / the Slave, the performance and ISP1161 (integrated host Solution Pairs 1161) rather
TDI: TransDimension Inc., a company that invented the first integrated EHCI RootHub the TT method, so that for an embedded system said, eliminating the need for OHCI / UHCI hardware, while reducing costs, as a memorial to the company, Linux kernel defines a macro ehci_is_TDI (ehci); product UHC124 expressed USB Host Controller; the acquisition of ARC USB technology; now chipidea acquisition, chipidea mips has been acquired
TLV: TI Low Value, cost-effective
TPS: TI Performance Solution
TT: transaction Translator (transaction converter converts the packets into USB2.0 USB1.1 package)
usb3_mifgen: Altera Memory the Initialization File
xECP: xHCI Extended Capabilities Pointer
