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diff --git a/board/glados_pd/dualtcpc.md b/board/glados_pd/dualtcpc.md deleted file mode 100644 index 80f1df7425..0000000000 --- a/board/glados_pd/dualtcpc.md +++ /dev/null @@ -1,119 +0,0 @@ -USB-C Dual TCPC Example -======================= - -This board configuration implements a USB-C TCPC for two ports. - -The design uses a microcontroller running code from the Chromium EC -codebase to implement the TCPC. The code tries to follow the "USB -Type-C Port Controller Interface Specification" that is released as -part of the -[USB 3.1 Specification](http://www.usb.org/developers/docs/). - -Building --------- - -### Chromium OS chroot - -All the following instructions have been verified in a Chromium OS -chroot. You can find how to set one up on the -[Chromium development -wiki](http://dev.chromium.org/chromium-os/quick-start-guide). - -### Build the TCPM code - -`cd src/platform/ec` - -`make BOARD=glados_pd` - - -Schematic ---------- - - - -Note that you may need to zoom in the browser to read the image if -reading this through the git source tree browser. A -[pdf of this schematic](glados_pd.pdf) is in the -[`board/glados_pd`](.) directory. It shows three main areas. - -The two (identical) sections on the left provide the analog interface -to the CC line. Each CC line is identical. Resistors are used in -combination to set the resistor applied to CC: - -Resistor |`USB_Cx_CCy_DEVICE_ODL`|`USB_Cx_CCy_HOST_HIGH`|Value ----------|-----------------------|----------------------|----- -1.5A Rp | high impedance | high 3.3V | 5.11k+6.98k pullup -3A Rp | high 3.3V | high impedance | 5.11k pullup -Rd | low 0V | high impedance | 5.11k pulldown - -When USB-PD transmission is required the `USB_Cx_CCy_MCU` is set low -and the data transmitted on `USB_Cx_CCy_TX_DATA`. The two resistors -form a divider that sets the level to match the BMC -specification. These resistors and the capacitor on the pulldown may -need tuning for a given application to meet the required TX eye mask. - -The `EN_PP3300_USB_PD` is a critical enable output from the MCU. It -must be pulled down when power is off (not shown here, it is done as -part of the load switch on the power supply page) and remains low -until the microcontroller is ready for operation. It: - -1. Enables the `PP3300_USB_PD` power supply that powers -all the USB-C port related components (eg the low speed mux `U24` -shown here and the high speed mux that is not part of this example -page) -2. Controls the isolation FET (two parts of `Q1`,two parts of `Q6`) to -disconnet the CC lines when power is off or the MCU is -intializing. When power is enabled the enable will put the gate at -3.3V and ensure no higher voltage on CC will reach the MCU. -3. Disables the Dead Battery pulldown once the MCU is ready for -operation. The Dead Battery Rd pulldown is provided by a FET (two -parts of `Q24` and `Q12`) and resistor. When there is no power, the -gate is pulled down to ground. A DFP application of Rp will pull up -the source and provide the required Vgs=-0.7 (Vgsth max should be 1V) -to turn on the FET and connect the Rd pulldown. Once there is power -and the MCU is running it will drive `EN_PP3300_USB_PD` high and -disable the FET. - -There is a load switch (`U9`,`U10`,`U11`,`U12`) to provide current -limited **Vconn**. - -The main area of the schematic is the STM32F051 microcontroller that -runs the [`glados_pd`](.) code. - -There is a quirk in `U24`. For port `C0` the transmit data is provided -by the SPI1 controller as `SPI1_MISO`. The internal I/O multiplex -allows this to be driven on either pin `PB4` or `PA6` and thus support -driving whichever CC line is needed. Port `C1` uses the SPI2 -controller which (on this package) can only use pin `PB14`, so an -external mux is used to direct this to the appropriate port. - -### Replacement with Two TCPC parts - -This schematic page can be replaced by two TCPC parts. - - - -Flashing and Running --------------------- - -### Flashing the firmware binary - -The microcontroller can be pre-programmed or is programmed in the -factory by pulling `USB_PD_BOOT0` high and resetting the part to -initiate a firmware update over UART. During development the -[Servo board](http://www.chromium.org/chromium-os/servo) can be used -for this. - -Once programmed for the first time, the part supports secure update of -the Read/Write copy. - -Known Issues ------------- - -1. This is the first version of the documentation... - - -Troubleshooting ---------------- - - |