This project is an example of FatFs on Raspberry Pi Pico by TinyGo.
- ported from elehobica/pico_fatfs_test
- confirmed with TinyGo 0.25.0
This project supports:
- FatFs R0.13c (http://elm-chan.org/fsw/ff/00index_e.html)
- SD card access by SPI interface
- SD, SDHC, SDXC cards
- FAT16, FAT32, exFAT formats
- write/read speed benchmark
- machine optimization by CGO to improve SPI access performance
- Raspberry Pi Pico
| Pico Pin # | Pin Name | Function | microSD connector | microSD SPI board |
|---|---|---|---|---|
| 4 | GP2 | SPI0_SCK | CLK (5) | CLK |
| 5 | GP3 | SPI0_TX | CMD (3) | MOSI |
| 6 | GP4 | SPI0_RX | DAT0 (7) | MISO |
| 7 | GP5 | SPI0_CSn | CD/DAT3 (2) | CS |
| 8 | GND | GND | VSS (6) | GND |
| 36 | 3V3(OUT) | 3.3V | VDD (4) | 3V3 |
- SPI0_TX and SPI0_RX needs to be pull-ed up with 10Kohm.
- Wire length between Pico and SD card is very sensitive. Short wiring as possible is desired, otherwise errors such as Mount error, Preallocation error and Write fail will occur.
| Pico Pin # | Pin Name | Function | CP2102 module |
|---|---|---|---|
| 1 | GP0 | UART0_TX | RXD |
| 2 | GP1 | UART0_RX | TXD |
| 3 | GND | GND | GND |
- Build is confirmed only in TinyGo Docker environment with Windows WSL2 integration
- Before starting docker, clone repository to your local enviroment (by GitBash etc.)
> cd /d/somewhere/share
> git clone -b main https://github.com/elehobica/pico_tinygo_fatfs_test.git
- Docker
> wsl
(in WSL2 shell)
$ docker pull tinygo/tinygo:0.25.0
$ docker images
$ docker run -it -v /mnt/d/somewhere/share:/share tinygo/tinygo:0.25.0 /bin/bash
(in docker container)
# cd /share
(copy repository for docker native directory for best performance of WSL2, otherwise stay /share)
(# cp -r /share/pico_tinygo_fatfs_test ~/ && cd ~ )
# cd pico_tinygo_fatfs_test
- Go Module Configuration
# go mod init github.com/elehobica/pico_tinygo_fatfs_test
# go mod tidy
- TinyGo Build
# tinygo build -target=pico --serial uart -opt 2 -o pico_tinygo_fatfs_test.uf2
(copy UF2 back to Windows local if working on docker native directory)
(# cp pico_tinygo_fatfs_test.uf2 /share/pico_tinygo_fatfs_test/ )
- Put UF2
Then, go back to Windows environment and put "pico_tinygo_fatfs_test.uf2" on RPI-RP2 drive
- Reference C++ pico_fatfs_test
=====================
== pico_fatfs_test ==
=====================
mount ok
Type is FAT32
Card size: 32.00 GB (GB = 1E9 bytes)
FILE_SIZE_MB = 5
BUF_SIZE = 512 bytes
Starting write test, please wait.
write speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
447.7192, 6896, 1007, 1142
446.4797, 7589, 1024, 1145
Starting read test, please wait.
read speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
974.9766, 1050, 403, 524
974.4066, 1049, 402, 524
- TinyGo (this repository)
============================
== pico_tinygo_fatfs_test ==
============================
mount ok
Type is FAT32
Card size: 32.00 GB (GB = 1E9 bytes)
FILE_SIZE_MB = 5
BUF_SIZE = 512 bytes
Starting write test, please wait.
write speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
390.2342, 17208, 1092, 1292
362.8215, 54979, 897, 1383
Starting read test, please wait.
read speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
835.5080, 16601, 554, 591
830.9257, 21483, 559, 594