Charger adapter for Xbox 360 battery pack

 

The battery charger in the Xbox 360 controller isn't exactly robust.  From time to time it would stop charging the NiMH battery pack.  This is a quick and dirty hack for a temporary charger that helps to charge the battery pack so that it can resume normal charging again.

I made this adapter from a 2 cell screw driver charge cradle.  Ironically there are no fancy electronics for charge termination.  The charger uses a small transformer and rectifier diodes without filter capacitor.  I would not recommend leaving the battery pack on the cradle for more than a few hours.

Charging indicator

I added a charging indicator.   The output voltage is a tad bit high for my liking. The negative terminal of the battery pack has a silicon diode in series for a bit of voltage drop and as a way to detect charge current. During charging, the transistor monitors the voltage drop across a silicon diode and turns on the high efficiency green LED.

I measured the dimensions of the cradle and the battery case using a slide caliper and 3D printed their counterparts using PLA+.  The cradle contacts are small strips of iron that was used to crimp the mesh bag for my onions.  The battery contact was dremel out from old ISA slot with 0.1" pitch. 

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The small PCB is soldered to the contacts and sit directly over it.

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Metal strips from onion bags are used as
the contacts  for the drill cradle

The previous version was hand made from an old dental floss case and through hole parts

Files are released on github

3D Printer Light Strip

I made a light strip for my 3D printer using parts I have lying around.  It uses a LDR for sensing the ambient light level and turns on.  It also shuts itself off for over-night print job when all other lights are off.

LED test - powered from a bench supply

The light strip consists of 3 PCB and a few 3D printed parts.

I used pieces of 12V LED strips soldered onto a PCB.   The strips are wired in series so that they would operate at 24V.

The 2 light strip PCB are assembled into the 2 PCB holder pieces with channels in the middle for wiring.  The are joint to a T shaped piece in the middle. The 2 side PCB are wired in parallel.  A 100K resistor (R9) has been added in parallel to the LED strips as the LED are sensitive enough to turns on through the 2200K feedback resistor.

The LED lightbar assembly is attached to the base with a M3 screw and a captured nut.  This forms an adjustable arm.

Here is the LTSpice simulation I used for the optional LED sensor.  The 2 comparators operates as a windows detector.  The lower threshold determines when the light turns on while the upper threshold is when all the lights are off.

As the LDR (R4) has a wide dynamic range, I have decided to inject the hysteresis at the reference by a positive feedback resistor R6.  It is driven from the MOSFET output which added a 180 degrees phase shift.  A capacitor C1 is added to suppress the oscillation during the on/off transitions.

V2 is used for simulating the LDR sensor by sweeping the range of voltages.

Blue trace: Comparator input
Green Trace: LED strip voltage

The following are the schematic and layout of the sensor.

The circuit  board is fasten to the  printed housing with double sided silicon adhesive tape.  The power switch is snapped into the opening in the front.   The circuit is powered from the internal 24V power supply located at the base of the printer just like the official lightbar. There is a connector for the 24V.

I used a heatshrink tubing to block off light entering to the sensor from the sides.

I routed the wires next to the one used by  filament sensor into the extruded aluminum frame on the left side.

This is a special one off design as the resistor values are empirically determined by the ambient light at my specific location and the electrical characteristics of the LDR I am using.  

I could have used trimpots for the thresholds.  The light sensor could have been implemented using a microcontroller like my Timer project.

Files are released under: https://github.com/FPGA-Computer/3D-Printer-projects/tree/master/Creality%20Ender%20V3%20KE/Lightbar

CH32V Development with Visual Studio Code/Platform IO: Set up and first impression

Prerequisite:

• Buy the WCH LinkE Emulation Debugger Module from the usual places from China for less than $5.  You won't even get to the bootstrap loader on the CH32V003 without one as there are no hardware bootstrap pins.  For higher end chips, the bootloader can download from USB using WCHISPTool.

Don't be temped by the cheaper older WCH Link module.  It is powered by CH549 (8051 core with 60K FLASH/2K RAM) It is not useful here but good for hacking it into CMSIS-DAP.

LinkE module is the one you want to get.  Powered by CH32V305 with 128K FLASH/32K RAM.  It supports for the low pin count parts that uses a single wire debug interface e.g. CH32V003 and newer chips e.g. CH32X035. 

• Download: WCH-Link Local Burning Tool: WCH-LinkUtility.ZIP from this page.  It'll also install a COM port driver.

Select WCH-LinkRV mode, hit Set.  The blue LED turns off.  This is now the default mode.

Hit Refresh, it now shows up as RISC-V Link.

 

Note: 

1. "Enable SDI Printf" option allows you to send debug messages on a virtual serial port piggy back on the SDI debugger interface (i.e. Semihosting). This is useful for low pin count parts. The support functions are described inside debug.h  See: https://www.cnblogs.com/liaigu/p/17628184.html  (use Chrome for translation)
2. WCH-LinkDAP-WINUSB mode is for debugging with CH32F (Arm) series.  
3. You can flash a new firmware and turning LinkE into a high-speed JTAG bridge similar to CH347 for DSP/FPGA using WCHLinkEJtagUpdTool.ZIP.  You'll need to re-flash the LinkE firmware to switch back.

• The instructions below requires Git pre-installed.  Git: https://git-scm.com/downloads  

Install IDE

• Install Visual Studio Code: https://code.visualstudio.com/ 

• Optional: Change PlatformIO Install Directory to path other than under your Windows user profile directory.  

Reference: https://community.platformio.org/t/vscode-install-directory/12325/2

Setting the PLATFORMIO_CORE_DIR pointing to my folder where the policies allow execution solves the issue. I set this value inside the standard Windows uservariables and then after this run the normal package installation process within VSCode.

Under Windows Advance User Setting/Environment Variable/User variable.  The highlighted path is where you want it.

Use Take Ownership on the directory if it is under "program files" to allow for write permission there.

• Install Extension: PlatformIO IDE (C/C++ Extension)
• Go to https://github.com/Community-PIO-CH32V/ch32-pio-projects   It is not yet in the official Platform IO, so follow the instructions to install the CH32V Platform. 

•  Optional: Change default project directory

See https://community.platformio.org/t/how-to-change-default-new-project-location/2828/18 

Hit the terminal icon on bottom to bring up this terminal.  For some reasons, this one works properly.

Type in the following and your directory path.  Add quotes around the path if there are any spaces.

pio settings set projects_dir  your_directory_path

PlatformIO.ini

There is a nasty surprise in the system_ch32v00x.c file. This is part of the startup code that is provided and set the SYSCLK prior to passing control to main(). 

The problem is that the default setting is for an external crystal connected to PA1 and PA2 pins.  If that assumption is incorrect, the 'RCC_HSERDY' bit will never be set. Their code doesn't handle the error properly.  Personally I prefer not having these hidden setting things up if I have to fix and handle the fail conditions.

If you don't want to edit the "system_ch32v00x.c" file, you can add a build_flags entries in the platformio.ini to add a compiler #define value.   You can use any of the listed options (line #20 - #25). I added the following:

build_flags = -D SYSCLK_FREQ_24MHZ_HSI

Creating a New Project

• Select Platform IO on the side bar (Ant Icon), hit "Create New Project".  Give it a name.
• Select "Generic CH32V003F4P6 (W.CH)" if you are using your own design or "CH32V003F4P6-EVT-R0 (W.CH)" for the eval board.
• There is choice for "Noneos-SDK" for bare metal or "Arduino" platform.  The Ch32V003 part is too small for other RTOS platforms.

My bare metal Blinky.  It toggles at 2MHz.

The debugger allows for the either source code level view or assembly, but not both.  The peripheral register  are shown grouped in fields and can be shown/modified when the program is paused or in single step.

Assembly language view but it doesn't have the source code reference like the other IDE I have used.

Some of the things I like about modern IDE over basic text editors.

It shows the macro definition, what it expands to and the enum values when you mouse over it.

Popup on mouse over function with doxygen comment - WCH HAL function

Update:

https://github.com/Community-PIO-CH32V/platform-ch32v/tree/develop?tab=readme-ov-file#updating

Other Links

https://github.com/gicking/CH32V003_examples - Port of original CH32V003 examples by WCH for PlatformIO.

CH32V003 tidbits

A minimalistic prototyping PCB can be made with a 0.1uF soldered onto pin 7 and 9 of a TSSOP-20 breakout board. The back side of the PCB contains SOIC pads that can be used for the 8 and 16 pins versions of the chip.  The chip can operate between 2.7V to 5V with the reset threshold programmable from 2.7V to 4.4V.

Minimalistic CH32V003 prototyping board

Core

QingKe V2 series microprocessor is a 32-bit general-purpose MCU microprocessor based on the standard 
RISC-V instruction subset RV32E(Base Integer Instruction Set) C(16-bit compression instruction) with only 16 general-purpose registers.

V2 series supports addition to custom XW extensions, Hardware Prologue/Epilogue (HPE), Vector Table Free (VTF), single-wire serial debug interface (SDI), and support for "WFE" instructions.

The following topics are covered in their QingKeV2_Processor_Manual 

Chapter 2 Exception 

Chapter 3 PFIC and Interrupt Control 

Chapter 4 System Timer (SysTick)

Chapter 5 Processor Low-power Settings 

Chapter 7 CSR Register List 

See reference manual for peripheral programming and application code example. The debug protocol and debug registers are documented in the RISC-V QingKeV2 Microprocessor Debug Manual.

The documentation is a bit minimal and I have to fill in some of the gaps. I use the STM32F103 Reference Manual as a fallback when the peripherals have same register offsets and bit definition as the STM32F103. e.g. I2C

GPIO

While CH32V003F4 pins are backward compatible with STM8F3 (TSSOP-20), 2 additional GPIO pins are available - VCAP pin is replaced as PD0 and NRST as PD7 (selectable via User Option Bytes) .

There are some GPIO input threshold differences between the STM8 and CH32V003.

I/O characteristics: STM8 has CMOS input threshold while CH32v003 has LVTTL threshold.

Note: Pull down resistors I normally use for push buttons on shared I/O needs to be below 8.9K as the internal pull-up = 30K (min).

3.3V * 8.9K /(8.9K + 30K) = 0.755V and 5V * 8.9K/(8.9K + 30K) = 1.144V

There are four 5V tolerant pins: PC1, PC2, PC5, PC6 (vs 2 in STM8) and up to 8 ADC pins. The alternate functions are more flexible as some can be mapped to additional GPIO pins. For the 20 pins package, Port C and D are rearranged as two contiguous 8-bit ports which make life easier for interfacing to byte-wise devices.

CH32V003F4P6 (TSSOP-20) GPIO pinout and their alternate functions

Option Byte Register

The following Option Bytes Register are the default setting when code is downloaded from the compiler/Debugger environment  Likely these are default factory setting. There doesn't seem to be a way of changing the values from within the IDE.

The Option Byte can be changed by reprogramming the FLASH inside the firmware. "USER and RDPRT are loaded from the user-option bytes area after a system reset".

The WCH-Link Utility can also be used to program the chip and for changing the FLASH Protection, Option Byte setting. "Reading Chip FLASH" doesn't update the GUI setting.

Option Byte Reset default setting from compiler

NRST pin

On the STM8, the NRST pin is also driven by a Open Drain driver (See STM8 Reference Manual Chapter 8 Reset) and asserted during a reset from internal source.  I use this pin on the STM8 and similarly on STM32F003 to reset LCD and OLED. 

It turns out that this is also the case for the CH32V003

CH32V003 Reset Structure

PD7/NRST pin is driven low during power up.  I have measured 16.27ms from power on to de-assertion of the Reset signal NRST on a single sample.  This agrees with the datasheet "Power on reset" parameter.

Trace 0: PD7/NRST without external capacitor

Trace 1: Vcc (3.3V) rail

3.3.2 Embedded reset and power control block characteristics. (Table 3-4)

Bootloader

The chip doesn't have a Boot pin to select Bootloader externally. Instead there is a non-volatile Mode bit that can be set to either jump to user code or bootload upon Reset.

See SystemReset_StartMode(uint32_t Mode) under  /EXAM/SRC/Peripheral/src/ch32v00x_flash.c in the application code example.

PlatformIO forum talks about how to modify the bootloader: here

Debricking

From EEVblog: Topic: CH32V003 -J4 (SOP8) pins (UPDATE: how to brick your -J4) 

WCH-Link Utility menu - Full Chip Erase

Resources:

There is a bit-bang USB implementation available in beta - RV003USB  This implementation looks much cleaner than the STM8 VUSB project that I have been using.  The USB pins are configurable in usb_config.h 

There is a CH32V003 F4P6 V-USB Development Board with the USB pins on PA1 and PA2.

I am having a lot of issues with this as it relies on ch32v003fun which pull in its own everything and doesn't play nice with PlatformIO or MounRiver.  Even after getting it to compile with no errors, my device isn't recognized.  I am hoping someone would remove the dependency.

It is back to STM8 or use a CH32X035 for me.

Alternate IDE:

Visual Studio Code using Platform IO plugin and Community-PIO-CH32V platform.

Upgrade path

The next cheapest upgrade is the CH32X035 or CH32X033 marketed as USB Connectivity parts.  They aren't pin compatible, but they can operate at 5V with the improved RISC-V core, FLASH, SRAM, ADC, UART, USB.

CH32X033/035 features

RV32I – Base Integer Instruction Set, 32-bit. Currently version 2.1
M – Standard Extension for Integer Multiplication and Division
A – Standard Extension for Atomic Instructions
C – Standard Extension for Compressed Instructions

The most accessible parts are the X033F8P6 and X035F7P6 TSSOP20 parts with cheaply available breakout boards.  I have originally ordered the TSSOP and find myself maxing out the GPIO very quickly for a couple of projects I have in mind.  I have ordered some QSOP28 but cannot find a cheap source for breakout boards. QSOP has a pin pitch of 0.635mm (0.025") which is slightly tighter than the 0.65mm pitch for TSSOP20 which I can manage with my home made PCB. Their 0.4mm pitched QFN parts on the other hand would require commercial quality PCB.

The USB bootloader is activated by pulling up on the USB D+ pin at power on.

The most uneventful WRT310N V2 8MB FLASH upgrade

 I bought this router at a thrift shop a long time ago for $5 mostly for its Gigabit Ethernet. It has been gathering dust as I have other ones with better specs.

Linksys WRT310N V2

Recently I need its 4MB FLASH for something else and my orders haven't came it.  I made a backup of the chip with my programmer.  3 months later, one of the orders finally showed up. I burnt a copy of the old 4MB image into a 8MB SPI FLASH: MX25L640EM2I.  It is important to keep the binary image of the chip as it contains some specific factory NVRAM settings e.g. MAC addresses that are not in the .trx file.

It boots up and showed 8MB in the status and managed to save a new setting. i.e. the FLASH chip is recognized.  I took a risk and upgrade to an image intended for 8MB device.  The worst that could happen is that I have to burn in a 4MB image and compile my own 8MB to support it.

It turns out that generic builds files with 32K NVRAM, MIPSR2 and without USB under the K26 directory works fine so far.  I picked the Max configuration with the full features set: 
freshtomato-K26-NVRAM32K_RT-MIPSR2-2023.1-Max.zip

It took about 90 seconds for the upgrade.  The most annoying part is to figure out the user name and password.  It took me quite a few tries as the username was changed to root from my previous firmware. Rest of it is uneventful.

It is good that the generic build recognizes the model as well as the correct FLASH size.

Status Overview showing router name and specs

Firmware version

The dreaded KB5034441 - what actually worked for me

Normally I don't talk much about fixing Windows problems as the tech blogs are a dime a dozen.  However, I have yet to find one that fixes the "0x80070643 - ERROR_INSTALL_FAILURE" with KB5034441. They seem all point to the WinRE partition wasn't sized sufficiently and each of them parroting the same stuff.  

I have resize the partition, but it still fails the update.  I have tried the PatchWinREScript_2004plus.ps1 from Microsoft, but it returned with a bunch of errors.  Obviously isn't fool proof enough for the end users.  I even ask Microsoft Copilot AI for a detail step by step instructions and it still isn't enough as there were errors in some of the steps.

I tried a whole bunch of things unsuccessfully and my WinRe was disabled.  I went through the usual long list of instructions trying to restore it manually e.g. extracting install.wim etc, but given up before I would do more damages. It is like a never ending quest like 50+ hours RPG with each quest requiring completing additional subtasks and no one have any up to date info.

What actually worked for me was to simply reinstall Windows. Obviously this is with the increased WinRe partition to 800MB and the install option of preserving the data and apps. This is the one with the least user interaction required, but no one else suggested this.

I let it install all the updates again and finally the dreaded KB installed properly. Whatever prerequisites that was broken along the way is now back to what they expect.  Don't forget to do a disk clean up for the old windows install and change back all your preferences that Windows like to muck with.

When in doubt, reinstall Windows.  :P