pico_sign_sipf_xmodem

README (日本語)

fig.1: horizontal scrolled image output on 480x1920 display at 20Hz where image can be updated via LTE

(picture on loading derived from http://panoroman.nao3.net/72/img_0485/)

what is this ?

show horizontal scrolled signboard on LCD display, powered by Raspberry Pi Pico and PicoDVI (https://github.com/Wren6991/PicoDVI)
PicoDVI feat/x8scale modified branch (https://github.com/homelith/PicoDVI/tree/feat/x8scale) enables expanding image 8 times large, saving memory capacity to 60x1280 image that fits limited memory capacity on Raspberry Pi Pico
signboard image will be updated via LTE, powered by SAKURA internet Mono Platform (https://iot.sakura.ad.jp/platform/) and its client device SCM-LTEM1NRF

building hardware (breadboard-based)

note
- DVI output tend to be unstable since breadboard has much poor signal transmission characteristics. Pray for success.
- HDMI-ish connector pin assignments are compatible with Pico DVI Sock (https://github.com/wren6991/pico-dvi-sock)
components
- Raspberry Pi Pico
- SCM-LTEM1NRF SAKURA internet Mono Platform evaluation module
  - currently anyone belongs to corporate entity can request one via https://iot.sakura.ad.jp/request_platform_devkit/ (they do not ship besides japan)
  - or you can purchase any number of units via third-party store (https://na-s.stores.jp/items/639927bd940f3d50b7c5a011)
  - assume generic sipf-std-client_nrf9160 firmware to be installed (https://github.com/sakura-internet/sipf-std-client_nrf9160)
  - tested with firmware on release v0.4.1 (https://github.com/sakura-internet/sipf-std-client_nrf9160/releases/tag/v0.4.1)
- Hannstar HSD088IPW1 + HDMI-HSD088-V05 480x1280 vertical elongated display
  - currently available on shigezone (https://www.shigezone.com/product/slimlcd/)
  - placing jumper on HDMI-ish connector 5V supply pin on HDMI-HSD088-V05 helps supplying power via HDMI cable
  - warning : this is out of HDMI standard (+5V line current is limited up to 50mA), use thicker and shorter cable or the cable may catch fire. TRY AT YOUR OWN RISK
  - generic 640x480 display can be alternative. To use them, modify PicoDVI parameters on sw/app/main.c
- HD03VLP20D HDMI signal breakout board
  - currently available on aitendo (https://www.aitendo.com/product/19221)
  - you can use Pico-DVI-Sock based extension (https://www.switch-science.com/products/7431) as an alternative and may get much higher signal integrity
- 5V DC power sources with 2 amps or more
- some dumper resisters (e.g. from 10 to 100 ohms) for DVI signals
- some tactile switches
- some jump wires
see docs/breadboard-sch.pdf for wiring

fig.2: experimental setup on breadboard

build software

prepare environment
- some linux based distros (tested under native ubuntu 20.04 LTS and WSL2 ubuntu 20.04 LTS)
- sudo apt install git gcc make cmake gcc-arm-none-eabi libnewlib-arm-none-eabi build-essential golang
compile uf2 binary
- you'll get sw/build/app/pico_sign_board.uf2 after compilation

$ git clone --recursive git@github.com:homelith/pico_sign_sipf_xmodem.git
$ cd pico_sign_sipf_xmodem/sw
$ make

convert source image
- prepare width 60px x height 1280px image as ${FILENAME}.png
- confirm generated binary has exactly 153600 bytes of size

$ cd pico_sign_sipf_xmodem/sw/tools/png2array
$ make
$ ./png2array -m rgb565 -f bin ${FILENAME}.png > ${FILENAME}.bin

run on device

download uf2 on Raspberry Pi Pico
- power on Pico with BOOTSEL button pressed to make Pico run on USB mass storage device mode
- place pico_sign_board.uf2 file on Pico-emulated USB storage root directory
- you will see "Pico Bitbang DVI" sample images scrolled horizontally
update signboard image
- assume SCM-LTEM1NRF module associated with a Mono Platform project and websocket service adapter on your SAKURA Cloud account.
- From project tab, upload ${FILENAME}.bin to associated project (fig.3)
- From service adapter tab, issue "send message to device" command (fig.4)
  - parameters : tags;{any 8bit hex value}, type;variable length string, value;${FILENAME}.bin
- Pico polls any new messages on every 3 minites by default or you can trigger it immediately by pressing tactile switch to drive Pico GP6 pin to GND.
- Once Pico found new messages with ${FILENAME}.bin, xmodem downloader will be initiated and the image will be updated consequently.
update signboard scroll speed
- default scroll speed 16 pixel/frame can be update via Mono Platform message struct
- assume SCM-LTEM1NRF module associated with a Mono Platform project and websocket service adapter on your SAKURA Cloud account.
- From service adapter tab, issue "send message to device" command.
  - parameters : tags;{any 8bit hex value}, type; int16 value, value; from -32768 to 32767
- Pico polls any new messages on every 3 minites by default or you can trigger it immediately by pressing tactile switch to drive Pico GP6 pin to GND.
- Once Pico found new messages with int16 value, scroll speed will be updated to {int16 value} pixel / frame.

fig.3: upload sign_board.bin on SAKURA Mono Platform project tab

fig.4: sending message on SAKURA Mono Platform service adapter tab, notifying device filename to be downloaded