These utilities were designed to work with Libre Computer OS images to control GPIO and various buses such as I2C, SPI, UART, and SDIO.
- Libre Computer board
- Libre Computer OS image or Raspbian adapted using Raspbian Portability tool
- Android, Armbian, CoreELEC, LibreELEC, Lakka are not supported!
- Translation from pin# or BCM (RPI) GPIO# to multiple output formats includeing sysfs, gpiod (chip+line), SoC ref, SoC ball, schematic ref, mux functions
- Getting and setting of GPIO pins that is not to be used as an API since performance cost of lookup is non-trivial
- GPIO LED sweep test to turn on and off header in sequence repeatedly
- YouTube Guide
- Drive modes, strength, biases
- gpioset modes
- active state
lgpio headers
lgpio header [HEADER]
lgpio info [HEADER] PIN [type=all,gpiod,chip,line,sysfs,name,pad,ref,desc]
lgpio get [HEADER] PIN
lgpio set [HEADER_][PIN]={0,1} [HEADER_][PIN]={0,1}
lgpio bcm [PIN] [TYPE={all,gpiod,chip,line,sysfs,name,pad,ref,desc}]
> lgpio headers
7J1
2J3
2J1
9J1
> lgpio header 7J1
Pin Chip Line sysfs Name Pad Ref Desc
1 3.3V 3.3V 3.3V 3.3V 3.3V VCC3.3V 3.3V
2 5V 5V 5V 5V 5V VCC5V 5V
3 0 5 506 GPIOAO_5 D13 I2C_SDA_AO I2C_SDA_AO // I2C_SLAVE_SDA_AO // UART_RX_AO_B
4 5V 5V 5V 5V 5V VCC5V 5V
5 0 4 505 GPIOAO_4 A10 I2C_SCK_AO I2C_SCK_AO // I2C_SLAVE_SCK_AO // UART_TX_AO_B
6 GND GND GND GND GND GND GND
7 1 98 499 GPIOCLK_0 E9 GPIOCLK_0 CLK24 // CLK12 // CLKOUT
8 1 91 492 GPIOX_12 A6 UART_A_TX UART_TX_A (long fifo) // SLIP_UART_TX
9 GND GND GND GND GND GND GND
10 1 92 493 GPIOX_13 B6 UART_A_RX UART_RX_A // SLIP_UART_RX
11 0 8 509 GPIOAO_8* F17 I2SOUT-CH23 2J1 SELECT // AO_CEC // EE_CEC // I2SOUT_CH23 // PWM_AO_A
12 0 6 507 GPIOAO_6 C11 PWM_F CLK_32K_IN // I2S_IN_01 // SPDIF_OUT // PWM_AO_B
13 0 9 510 GPIOAO_9 C12 I2SOUT-CH45 REMOTE_OUTPUT // PWM_AO_B // I2SOUT_CH45 // SPDIF_OUT
14 GND GND GND GND GND GND GND
15 0 10 511 TEST_N** B12 I2SOUT-CH67 **PULL LOW RESET** // WATCHDOG // GPOAO_14 // I2SOUT_CH67
16 1 93 494 GPIOX_14 C6 UART_A_CTS_N UART_CTS_A // SLIP_UART_CTS
17 3.3V 3.3V 3.3V 3.3V 3.3V VCC3.3V 3.3V
18 1 94 495 GPIOX_15 C7 UART_A_RTS_N UART_RTS_A // SLIP_UART_RTS
19 1 87 488 GPIOX_8 B4 BTPCM_DOUT PCM_OUT_A // UART_TX_C // SPI_MOSI // TSin_SOP_A
20 GND GND GND GND GND GND GND
21 1 88 489 GPIOX_9 B3 BTPCM_DIN PCM_IN_A // UART_RX_C // SPI_MISO // Tsin_D_VALID_A
22 1 79 480 GPIOX_0 A2 WIFI_SD_D0 SDIO_D0
23 1 90 491 GPIOX_11 C4 BTPCM_CLK PCM_CLK_A // UART_RTS_C // SPI_SCLK // TSin_CLK_A
24 1 89 490 GPIOX_10 C5 BTPCM_SYNC PCM_FS_A // UART_CTS_C // SPI_SS0 // TSin_D0_A
25 GND GND GND GND GND GND GND
26 1 80 481 GPIOX_1 C3 WIFI_SD_D1 SDIO_D1
27 1 75 476 GPIODV_26 E2 I2C_SDA_A UART_CTS_B // I2C_SDA_B
28 1 76 477 GPIODV_27 F3 I2C_SCK_A UART_RTS_B // I2C_SCK_B
29 1 96 497 GPIOX_17 B5 BT_EN BT_EN
30 GND GND GND GND GND GND GND
31 1 97 498 GPIOX_18 B7 BT_WAKE_HOST BT_WAKE_HOST
32 1 95 496 GPIOX_16 A3 WIFI_32K PWM_E
33 1 85 486 GPIOX_6 D2 WIFI_PWREN PWM_A
34 GND GND GND GND GND GND GND
35 1 86 487 GPIOX_7 C1 WIFI_WAKE_HOST SDIO_IRQ // PWM_F
36 1 81 482 GPIOX_2 C2 WIFI_SD_D2 SDIO_D2
37 1 84 485 GPIOX_5 D3 WIFI_SD_CMD SDIO_CMD
38 1 82 483 GPIOX_3 B1 WIFI_SD_D3 SDIO_D3
39 GND GND GND GND GND GND GND
40 1 83 484 GPIOX_4 B2 WIFI_SD_CLK SDIO_CLK
> lgpio info 7J1 3
Chip Line sysfs Name Pad Ref Desc
0 5 506 GPIOAO_5 D13 I2C_SDA_AO I2C_SDA_AO // I2C_SLAVE_SDA_AO // UART_RX_AO_B
> lgpio info 3
Chip Line sysfs Name Pad Ref Desc
0 5 506 GPIOAO_5 D13 I2C_SDA_AO I2C_SDA_AO // I2C_SLAVE_SDA_AO // UART_RX_AO_B
> lgpio get 7J1 3 # Do not use this as an API call. The overhead of lookup is non-trivial.
1
> lgpio get 3 # Do not use this as an API call. The overhead of lookup is non-trivial.
1
> lgpio set 7J1_3=1 7J1_5=1 # Do not use this as an API call. The overhead of lookup is non-trivial.
> lgpio set 3=1 5=1 # Do not use this as an API call. The overhead of lookup is non-trivial.
> lgpio bcm 2 # Translate from BCM (RPI) GPIO# instead of pin #
Chip Line sysfs Name Pad Ref Desc
0 5 506 GPIOAO_5 D13 I2C_SDA_AO I2C_SDA_AO // I2C_SLAVE_SDA_AO // UART_RX_AO_B
> lgpio bcm 2 sysfs # Get the deprecated sysfs interface number from BCM (RPI) GPIO# for use with /sys/class/gpio/export
506- I2C
- SPI
- UART
- PWM
- SDIO
- SPI frequency and mode test
- YouTube Guide
./ldto list # lists overlays
./ldto status # returns list of active overlays
./ldto active [OVERLAY] # returns list of active overlays, if OVERLAY is specified: returns 0 if active, 1 if inactive
sudo ./ldto enable OVERLAY # apply overlay temporarily, effective until reboot
sudo ./ldto disable OVERLAY # remove temporary overlay, can crash system if overlay is hardware based
sudo ./ldto current # show current system device tree
sudo ./ldto merge OVERLAY # apply overlay permanently, effective after reboot
./ldto show # show new system device tree effective after reboot
sudo ./ldto diff # show difference between running device tree and new device tree effective after reboot
sudo ./ldto reset # remove all overlays, effective after rebootBoard-agnostic alias maps allow for programs to enable hardware without detecting the board and/or specifying overlay names. The 40-pin header found on many of our boards have similar hardware functions on specific pins and a few are described below.
H40P_I2C_0 - I2C bus on pin 3 and pin 5
H40P_I2C_1 - I2C bus on pin 27 and pin 28
H40P_SPI_0_1CS - SPI bus on pins 19, 21, 23 with chip enable on pin 24
H40P_SPI_0_1CS_DEV - SPI bus on pins 19, 21, 23 with chip enable on pin 24 userspace spidev node
H40P_SPI_0_2CS - SPI bus on pins 19, 21, 23 with chip enables on pins 24, 26
H40P_SPI_0_2CS_DEV - SPI bus on pins 19, 21, 23 with chip enables on pins 24, 26 userspace spidev node
H40P_UART0 - UART on pins 8, 10
H40P_PWM_Px - PWM on pin X*
Please be aware that certain PWM controllers offer two outputs that use a different overlays. Only use one PWM alias if you did not check the overlays for a specific board.
- Support for additional device tree overlays
- Device Tree Overlay service to read Raspbian config.txt and apply corresponding overlay on bootup