Add support for Spotpear HDMI board

[jeffbrl]

I'm interested in adding support for this HDMI board (https://spotpear.com/index/study/detail/id/971.html). I wanted to get feedback on my thinking about how this would be done.

Would this be as simple as adjusting the code for the Adafruit DVI board to map to different pins?

      Adafruit   Spotpear
D0+   GPIO12     GPIO11

D0-   GPIO13     GPIO10

CK+   GPIO14     GPIO9

CK-   GPIO15     GPIO8

D2+   GPIO16     GPIO15

D2-   GPIO17     GPIO14

D1+   GPIO18     GPIO13

D1-   GPIO19     GPIO12

If it is this simple, I may be able to submit the PR myself. :-)

[fhoedemakers]

I could add it, but don't have the board at hand. You also need an sdcard break out. Also I'm in the middle of a big merge i plan to do the next couple of days. So your PR will be conflicting i guess

Add this to pico_shared/dvi_configs.h

constexpr dvi::Config dviConfig_spotpear= {
.pinTMDS = {11, 13, 15},
.pinClock = 9,
.invert = true,
};

Then add a new board config in pico_shared/BoardConfigs.cmake with DVICONFIG=dviConfig_spotpear and add the correct gpio settings for your sd card. Also set the NES_ and WII_ variables to -1 if you don''t use a NES controller or WII-classic controller.
Also build scripts need to be changed.

[fhoedemakers]

I think you are using an old version of the Pico SDK. Please install the latest version and try again.Verstuurd vanaf mijn iPhoneOp 6 aug 2025 om 19:58 heeft Jeff Loughridge ***@***.***> het volgende geschreven: @fhoedemakers Thank you for the detailed instructions. I made the changes you suggested in a local feature branch. The build scripts are giving me troubles. I checked out the main branch to test compilation sans my edits. Looks like my toolchain is not properly configured as I'm getting an error related to pioasm. $ ./buildAll.sh Building piconesPlus Using Pico SDK version: 1 Building for pico, platform rp2040 with RELEASE configuration and HWCONFIG=1 UF2 file: pico_piconesPlusPimoroniDV.uf2 * Adding build types... * Current build type is : RELEASE [snip] [100%] Built target pioasm [ 15%] No install step for 'PioasmBuild' [ 16%] Completed 'PioasmBuild' [ 16%] Built target PioasmBuild [ 17%] Generating dvi_serialiser.pio.h [ 18%] Generating audio_i2s.pio.h [ 19%] Generating spi.pio.h /home/jeffl/development/pico-infonesPlus/pico_shared/drivers/pico_fatfs/pio/spi/spi.pio:12.1-12: unknown directive .pio_version 12 | .pio_version 0 // only requires PIO version 0 | ^~~~~~~~~~~~ make[2]: *** [pico_shared/drivers/pico_fatfs/pio_spi/CMakeFiles/pio_spi_spi_pio_h.dir/build.make:73: pico_shared/drivers/pico_fatfs/pio_spi/spi.pio.h] Error 1 make[1]: *** [CMakeFiles/Makefile2:1930: pico_shared/drivers/pico_fatfs/pio_spi/CMakeFiles/pio_spi_spi_pio_h.dir/all] Error 2 make[1]: *** Waiting for unfinished jobs.... [ 19%] Built target dvi_dvi_serialiser_pio_h [ 19%] Built target pico_audio_i2s_audio_i2s_pio_h make: *** [Makefile:91: all] Error 2 $ To my knowledge, I've followed the instructions in the Building from Source section including installation of the RISCV toolchain. —Reply to this email directly, view it on GitHub, or unsubscribe.You are receiving this because you were mentioned.Message ID: ***@***.***>

[jeffbrl]

Yes, I realized that I'd checked out an older version of the SDK immediately after I hit "Reply". Now I no longer get that error but I get other ones (potentially related to SDK version as well). Any chance you have a docker container that can be used to build pico-infoNES? If not, may I get the git tag of the Pico SDK version you are using?

[fhoedemakers]

2.1.1 togheter with the latest master of tinyusbI use WSL in stead of docker for development. For releases I use self hosted actions on a raspberry pi (Debian)What errors do you get?Verstuurd vanaf mijn iPhoneOp 6 aug 2025 om 20:17 heeft Jeff Loughridge ***@***.***> het volgende geschreven: Yes, I realized that I'd checked out an older version of the SDK immediately after I hit "Reply". Now I no longer get that error but I get other ones (potentially related to SDK version as well). Any chance you have a docker container that can be used to build pico-infoNES? If not, may I get the git tag of the Pico SDK version you are using? —Reply to this email directly, view it on GitHub, or unsubscribe.You are receiving this because you were mentioned.Message ID: ***@***.***>

[fhoedemakers]

I noticed there are build errors when using the latest Pico SDK 2.2.0 which was released some days ago.
Building using SDK 2.1.1 works fine.

[ 68%] Building ASM object CMakeFiles/piconesPlus.dir/pico_lib/dvi/tmds_encode.S.o
/home/pi/pico-sdk2.2.0-tusb-latest/src/boards/include/boards/pico.h: Assembler messages:
/home/pi/pico-sdk2.2.0-tusb-latest/src/boards/include/boards/pico.h:17: Error: bad instruction pico_board_cmake_set(PICO_PLATFORM, rp2040)' /home/pi/pico-sdk2.2.0-tusb-latest/src/boards/include/boards/pico.h:75: Error: bad instruction pico_board_cmake_set_default(PICO_FLASH_SIZE_BYTES, (210241024))'
make[2]: *** [CMakeFiles/piconesPlus.dir/build.make:1086: CMakeFiles/piconesPlus.dir/pico_lib/dvi/tmds_encode.S.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [CMakeFiles/Makefile2:2087: CMakeFiles/piconesPlus.dir/all] Error 2
make: *** [Makefile:91: all] Error 2

[jeffbrl]

Yes, I noticed the same. I used v2.1.1. I am able to execute a successful build manually using mkdir build && cd build && cmake -D DVICONFIG=dviConfig_spotpear .. When I power up the pico, I do not get any video.

I have a few questions for you.

1. Was your recommended changed to the dvi::Config struct based on my thinking from my original message or a review of the spotbear DVI data sheet?

2. Do you have recommendations for troubleshooting? From what I can tell, there is no output on the serial console.

[fhoedemakers]

Hi,

The dvi::Config I provided was based on the Spotpear datasheet.

I'm not sure whether the CMake arguments you specified will work. Can you send me the CMakeLists and pico_shared/BoardConfigs.cmake?

In pico_shared/BoardConfigs.cmake, you need to add a new HW_CONFIG configuration, as shown here:

add a elseif (HW_CONFIG EQUAL N ) where N is the next highest number. Copy/Paste an exsting block and change the contents.

There, you need to set DVICONFIG to dviconfig_spotpear and configure the correct GPIO settings for your SD card reader. Also set UART_ENABLED to 1, the NES_ and WII_ variables to -1 if you don't use vintage NES controllers or WI-Classic controllers and leave USE_I2S_AUDIO to 0.

Next, in CMakeLists.txt in the root folder of the pico-infoNesPlus repository, you can change your default configuration and Pico board:

Set HW_CONFIG to the number of the configuration you added in pico_shared/BoardConfigs.cmake and depending on your board type Set PICO_BOARD to pico, pico_w, pico2 or pico2_w

then you can simply run cmake from the build directory without any further arguments. Best to remove the entire contents first:

cd build
rm -rf *
cmake ..

It’s strange that you’re not seeing any serial output. Make sure UART is enabled for your configuration, and that you’ve connected GPIO0 and GPIO1 to a terminal. (I use a Pico Debug Probe for this.)

set(UART_ENABLED 1 CACHE STRING "Enable UART output") 

Although nothing is shown on the screen, do you still see the LED blinking? This indicates that the emulator is running, but the DVI configuration is incorrect. If the LED is not blinking, the program has almost certainly crashed.

Note that using a build for pico on a pico_w will also result in no blinking LED, even though the emulator should otherwise run fine.

An incorrect pin configuration for your SD card reader can also crash the software.
Usually, this will trigger an error message on the screen (if working) and over UART, but not always. What sdcard board are you using?

Attaching a debugger or getting serial UART output working can be very helpful for troubleshooting.

[jeffbrl]

https://github.com/jeffbrl/pico-infonesPlus/blob/feat-spotbear-support/CMakeLists.txt
https://github.com/jeffbrl/pico-infonesPlus/blob/feat-spotbear-support/pico_shared_vendored/BoardConfigs.cmake

I'm manually copying files between my pico_shared_vendored and pico_shared because I didn't properly get rid of the submodule, and it won't let me commit files in a directory called pico_shared.

Blinky light. I didn't connect to UART0 TX/RX. I thought a serial port might be available on USB. I have a pico that I use as a debug probe. I can hook that up when I have some time.

I don't have my SD card reader hooked up yet. I was thinking that I should confirm video is working before I hook it up.

[jeffbrl]

I have the pico hooked up to a programmer that can do SWD and also UART. While the LED blinks, I am not getting anything on the UART at 9600 and 115200 baud. I have set(UART_ENABLED 1 CACHE STRING "Enable UART output") under new HW_CONFIG 7 section in BoardConfigs.cmake. I believe the SWD set up is working so I could use GDB to debug but I do not know what to look for. Do you have any suggestions?

[fhoedemakers]

The blinking LED indicates that the program is running. Since you’re not getting any image, the most likely cause is an incorrect GPIO configuration for the display in the software. Another possible issue could be missing 5 V supply to the HDMI board, but I don’t think that’s the case here.

If the SD card is not connected, you should normally see a mount error displayed on screen (see this code snippet). So i think the code is executing the DisplayFatalError routine.

---

Please send me:

• boardsconfigs.cmake
• The top-level CMakeLists.txt from the root of the repo
• The CMake output

---

I also don’t understand why the serial output isn’t working over GPIO0/GPIO1.
With UART_ENABLED=1, it should work—provided you’ve connected:

• GPIO0 (TX) → programmer RX
• GPIO1 (RX) → programmer TX
• GND pin → programmer GND

At the moment the software is configured to only use UART0 GPIO0/GPIO1 for serial output. So you must use these pins.

[jeffbrl]

https://github.com/jeffbrl/pico-infonesPlus/blob/feat-spotbear-support/CMakeLists.txt
https://github.com/jeffbrl/pico-infonesPlus/blob/feat-spotbear-support/pico_shared_vendored/BoardConfigs.cmake

$ cmake  -D DVICONFIG=dviConfig_spotpear ..
* Adding build types...
* Current build type is : Debug
Hardware configuration: 7
Pico SDK board type   :
Tinyusb board type    : pico_sdk
PIO USB is disabled, using default USB driver.
HDMI board type       : dviConfig_spotpear
SD card CS            : 5
SD card SCK           : 2
SD card MOSI          : 3
SD card MISO          : 4
SD card SPI           : spi0
NES controller 0 CLK  : 6
NES controller 0 DATA : 7
NES controller 0 LAT  : 8
NES controller 0 PIO  : pio0
NES controller 1 CLK  : 9
NES controller 1 DATA : 10
NES controller 1 LAT  : 11
NES controller 1 PIO  : pio1
Wii controller SDA    : -1
Wii controller SCL    : -1
Wii controller I2C    : i2c1
LED pin               : 0
UART output enabled   : 1
I2S Audio enabled     : 0
I2S audio data pin    : -1
I2S audio clock pin   : -1
I2S audio PIO         : 1
I2S audio clock swap  : 0
PSRAM chip select pin : 47
PICO_BOARD not set, using default: pico
Mapper 5 enabled      : 0
PICO_SDK_PATH is /home/jeffl/pico/pico-sdk
Target board (PICO_BOARD) is 'pico'.
Using board configuration from /home/jeffl/pico/pico-sdk/src/boards/include/boards/pico.h
Defaulting platform (PICO_PLATFORM) to 'rp2040' based on PICO_BOARD setting.
Defaulting compiler (PICO_COMPILER) to 'pico_arm_cortex_m0plus_gcc' since not specified.
Configuring toolchain based on PICO_COMPILER 'pico_arm_cortex_m0plus_gcc'
Compiling TinyUSB with CFG_TUSB_DEBUG=1
Defaulting PICO_GCC_TRIPLE to 'arm-none-eabi'
-- The C compiler identification is GNU 12.2.1
-- The CXX compiler identification is GNU 12.2.1
-- The ASM compiler identification is GNU
-- Found assembler: /usr/bin/arm-none-eabi-gcc
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/arm-none-eabi-gcc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /usr/bin/arm-none-eabi-g++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
Build type is Debug
Using regular optimized debug build (set PICO_DEOPTIMIZED_DEBUG=1 to de-optimize)
-- Found Python3: /usr/bin/python3 (found version "3.11.2") found components: Interpreter
TinyUSB available at /home/jeffl/pico/pico-sdk/lib/tinyusb/src/portable/raspberrypi/rp2040; enabling build support for USB.
BTstack available at /home/jeffl/pico/pico-sdk/lib/btstack
cyw43-driver available at /home/jeffl/pico/pico-sdk/lib/cyw43-driver
lwIP available at /home/jeffl/pico/pico-sdk/lib/lwip
mbedtls available at /home/jeffl/pico/pico-sdk/lib/mbedtls
Using PICOTOOL_FETCH_FROM_GIT_PATH from environment ('/home/jeffl/pico/pico-from-git')
-- Using custom lwmem_opts.h file from /home/jeffl/development/pico-infonesPlus/pico_shared/lwmem_opts_ppp.h
-- Configuring done
-- Generating done
-- Build files have been written to: /home/jeffl/development/pico-infonesPlus/build
$

[fhoedemakers]

The NES controller GPIO pins conflict with the Spotpear HDMI GPIO pins, so they cannot be used together.
Set both NES_CLK and NES_CLK_1 to -1 in BoardConfigs.cmake.
If you plan to use NES controllers, you must assign them to free GPIO pins..

[jeffbrl]

Thank you, @fhoedemakers . I made the changes you suggested. Still no video or output from UART. Perhaps I should give up and buy a supported board. 😊

[fhoedemakers]

I just ordered a spotpear board. Will see if i can make it work.

[jeffbrl]

@fhoedemakers Wow, that was unexpected. I hope you are successful and that other people will benefit from Spotpear support other than just me.

[fhoedemakers]

One final note: when building with CMake, make sure to delete the contents of the build folder first. The variables mentioned earlier are cached, so changes to it in BoardConfigs.cmake won’t be applied if the old values are still present.

[fhoedemakers]

Hi,

I received the Spotpear boards from China this week and managed to get it working.
According to the schematic, the HDMI pin layout should be:

pinTMDS = {11, 13, 15}, pinClock = 9, invert = true

However, this is incorrect. The correct configuration is:

pinTMDS = {10, 12, 14},  pinClock = 8, invert = true

Below you’ll find a ZIP file containing precompiled .uf2 executables for both the Pico (RP2040) and Pico2 (RP2350):

piconesPlus_SpotpearHDMI.zip

Note: The Spotpear has a quirk where BOOTSEL does not work if an HDMI cable is plugged in. Make sure to unplug the HDMI cable before powering on with BOOTSEL pressed.

For prototyping I used a Pimoroni Pico Omnibus. The small board dangling in the photo is an SD card reader – specifically this one

If no SD card reader is connected, you’ll see an “SD card mount error” message on the screen.

Please let me know your feedback.

I have two branches setup for this so you can look for your self:

• https://github.com/fhoedemakers/pico-infonesPlus/tree/spotpear
• https://github.com/fhoedemakers/pico_shared/tree/spotpear

[jeffbrl]

First off, thank you very much @fhoedemakers for all the guidance, ordering the board and writing the code.

With your binary I see the expected SD card mount error. I will wire up the SD card.

My unit does not exhibit the BOOTSEL problem you noticed. I ordered mine several years ago so perhaps there are different HW revisions.

Will you be creating a PR to merge the spotpear code? If there are ways I can support you either in testing or documentation, I'd be glad to help out. I wouldn't be able to offer much help on the build scripts as cmake is not an area of expertise for me.

[fhoedemakers]

I’ve merged the code into main.
Yes certainly:
Could you update the README with the new config? Maybe add a picture of your Spotpear setup and explain how you wired it up. Also, include which GPIO pins are used for the SD card board. That would be great if you could do that.

I know the README feels a bit overwhelming right now. I might create a wiki in the future to make things easier to follow.

[jeffbrl]

Sure, I will submit a PR for spotpear-related README updates

[jeffbrl]

picoNES is unable to mount the FAT32-formatted SD card. My wiring is as follows.

CS --> GPIO5
CLK --> GPIO2
MOSI --> GPIO3
MISO --> GPIO4
VCC --> 3V3_OUT (tried VBUS as well)
GND --> GND

I suspect my SD card reader isn't functioning. I will order another reader and give it a shot.

[fhoedemakers]

Yes that should be right.