Expanders Tiger City IMX Industrial Computer with Linux OS Expander A Expander B Expander C Expander D Expander E Expander F Expander A Part number: 74HC595BQ Expander A diagram Expander A pins description Pin Type Usage User-space name Description 1 Q1 DO1 gpiochip8 1 Digital output 1 2 Q2 DO2 gpiochip8 2 Digital output 2 3 Q3 DO3 gpiochip8 3 Digital output 3 4 Q4 DO4 gpiochip8 4 Digital output 4 5 Q5 DO5 gpiochip8 5 Digital output 5 6 Q6 DO6 gpiochip8 6 Digital output 6 7 Q7 DO7 gpiochip8 7 Digital output 7 9 Q7S NC X Not connected 10 MR/ NRST_GLOBAL X Reset 11 SHCP SPI1_SCLK X SPI clock 12 STCP SPI1_CS1 X SPI chip select 13 OE/ GND X Output enable 14 DS SPI1_MOSI X SPI master out slave in 15 Q0 MUX_DIO_SEL gpiochip8 0 MUX_PWM selection signal 16 VCC +3V3 X Power supply SPI1 Signal Processor pin Default function Chip select 0 AD18 SPI1_CS0 Chip select 1 AG23 SPI1_CS1 Master in slave out A7 SPI1_MISO Clock D6 SPI1_SCLK Master out slave in B7 SPI1_MOSI Expander B Part number:  SC16IS752IBS Expander B diagram Expander B pins description Pin Type Usage User-space name Description 1 RXA(I) RS485_UART1_RX X RS485 UART1 RX 2 RESET/ RS485_NRST X Reset 3 XTAL1(I) TXCO_OUT X Oscillator output 4 XTAL2(O) NC X Not connected 5 VDD +3V3 X Power supply 6 I2C / SPI/ GND X Ground 7 CS/ / A0 SPI2_CS1 X SPI chip select 8 SI / A1 SPI2_MOSI X SPI master out slave in 9 SO SPI2_MISO X SPI master in slave out 10 SCL / SCLK SPI2_SCLK X SPI clock 11 SDA / VSS GND X Ground 12 VSS GND X Ground 14 IRQ/ RS485_INT X RS485 interrupt 15 CTSB/ NC X Not connected 16 RTSB/ RS485_UART2_RTS X RS485 UART2 RTS 17 GPIO0 / DSRB/ NC X Not connected 18 GPIO1 / DTRB/ NC X Not connected 19 GPIO2 / CDB/ NC X Not connected 20 GPIO3 / RIB/ NC X Not connected 22 TXB(O) RS485_UART2_TX X RS485 UART2 TX 23 RXB(I) RS485_UART2_RX X RS485 UART2 RX 24 GPIO4 / DSRA/ NC X Not connected 25 GPIO5 / DTRA/ NC X Not connected 26 GPIO6 / CDA/ NC X Not connected 27 GPIO7 / RIA/ NC X Not connected 30 RTSA/ RS485_UART1_RTS X RS485 UART1 RTS 31 CTSA/ NC X Not connected 32 TXA(O) RS485_UART1_TX X RS485 UART1 TX SPI2 Signal Processor pin Default function Chip select 0 A6 SPI2_CS0 Chip select 1 AF12 SPI2_CS1 Chip select 2 AB19 SPI2_CS2 Master in slave out A8 SPI2_MISO Clock E6 SPI2_SCLK Master out slave in B8 SPI2_MOSI Expander C Part number: MCP23017-E/ML Expander C diagram Expander C pins description Pin Port Type User-space name Description 1 GPB4 GPIO gpiochip5 12 UIO4 voltage 2 GPB5 GPIO gpiochip5 13 UIO4 current 3 GPB6 GPIO gpiochip5 14 UIO4 resistance 4 GPB7 GPIO gpiochip5 15 UIO3 resistance 5 VDD +3V3 X Power supply 6 VSS GND X Ground 7 NC NC X Not connected 8 SCK GPIO X I2C clock 9 SDA GPIO X I2C data 10 NC NC X Not connected 11 A0 GND X Address bit 0 12 A1 GND X Address bit 1 13 A2 GND X Address bit 2 14 RESET/ EXP2_NRST X Reset 15 INTB NC X Not connected 16 INTA NC X Not connected 17 GPA0 GPIO gpiochip5 0 UIO2 resistance 18 GPA1 GPIO gpiochip5 1 UIO1 resistance 19 GPA2 GPIO gpiochip5 2 UIO1 voltage 20 GPA3 GPIO gpiochip5 3 UIO2 voltage 21 GPA4 GPIO gpiochip5 4 UIO3 voltage 22 GPA5 GPIO gpiochip5 5 UIO1 current 23 GPA6 GPO gpiochip5 6 UIO4 I source 24 GPA7 GPIO gpiochip5 7 UIO3 current 25 GPB0 GPIO gpiochip5 8 UIO2 current 26 GPB1 GPO gpiochip5 9 UIO1 I source 27 GPB2 GPO gpiochip5 10 UIO2 I source 28 GPB3 GPO gpiochip5 11 UIO3 I source I2C2 Device name: /dev/i2c-1 Signal Processor pin Default function Clock D10 I2C2_SCL Data D9 I2C2_SDA Expander D Part number: MCP23017 Expander D diagram Expander D pins description Pin Port Type User-space name Description 1 GPB4 GPO gpiochip6 12 LED3 BLUE ON / OFF 2 GPB5 GPO gpiochip6 13 LED4 GREEN ON / OFF 3 GPB6 GPO gpiochip6 14 OLED ON / OFF 4 GPB7 GPO gpiochip6 15 LED4 BLUE ON / OFF 5 VDD +3V3 X Power supply 6 VSS GND X Ground 7 NC1 NC X Not connected 8 SCK GPIO X I2C clock 9 SDA GPIO X I2C data 10 NC2 NC X Not connected 11 A0 GND X Address bit 0 12 A1 GND X Address bit 1 13 A2 GND X Address bit 2 14 RESET/ NRST_GLOBAL X Reset 15 INTB HMI_IRQ X Interrupt B 16 INTA HMI_IRQ X Interrupt A 17 GPA0 GPI gpiochip6 0 Joystick left input 18 GPA1 GPI gpiochip6 1 Joystick up input 19 GPA2 GPI gpiochip6 2 Joystick down input 20 GPA3 GPI gpiochip6 3 Joystick right input 21 GPA4 GPI gpiochip6 4 Joystick push input 22 GPA5 GPO gpiochip6 5 LED3 RED ON / OFF 23 GPA6 GPI gpiochip6 6 DIP switch 6 input 24 GPA7 GPI gpiochip6 7 DIP switch 7 input 25 GPB0 GPI gpiochip6 8 DIP switch 8 input 26 GPB1 GPO gpiochip6 9 LED 5 V power supply ON / OFF 27 GPB2 GPO gpiochip6 10 LED3 GREEN ON / OFF 28 GPB3 GPO gpiochip6 11 LED4 RED ON / OFF I2C3 Device name: /dev/i2c-2 Signal Processor pin Default function Clock E10 I2C3_SCL Data F10 I2C3_SDA Expander E Part number:  MCP23017-E/ML Expander E diagram Expander E pins description Pin Port Type User-space name Description 1 GPB4 GPI gpiochip5 12 Digital input 4 (DIO circuit) 2 GPB5 GPI gpiochip5 13 Digital input 5 (DIO circuit) 3 GPB6 GPI gpiochip5 14 Digital input 6 (DIO circuit) 4 GPB7 GPI gpiochip5 15 Digital input 7 (DIO circuit) 5 VDD +3V3 X Power supply 6 VSS GND X Ground 7 NC NC X Not connected 8 SCK GPIO X I2C clock 9 SDA GPIO X I2C data 10 NC NC X Not connected 11 A0 +3V3 X Address bit 0 12 A1 +3V3 X Address bit 1 13 A2 GND X Address bit 2 14 RESET/ EXP1_NRST X Reset 15 INTB GPIO_EXP_INT X Interrupt B 16 INTA GPIO_EXP_INT X Interrupt A 17 GPA0 GPO gpiochip5 0 Termination RS485_4 ON / OFF 18 GPA1 GPO gpiochip5 1 Termination RS485_3 ON / OFF 19 GPA2 GPO gpiochip5 2 Termination RS485_2 ON / OFF 20 GPA3 GPO gpiochip5 3 Termination RS485_1 ON / OFF 21 GPA4 NC X Not connected 22 GPA5 NC X Not connected 23 GPA6 GPO gpiochip5 6 Secure chip idle/busy 24 GPA7 GPI gpiochip5 7 Digital input 1 (DIO circuit) 25 GPB0 GPO gpiochip5 8 Digital input 2 (DIO circuit) 26 GPB1 GPI gpiochip5 9 SD detect 27 GPB2 GPI gpiochip5 10 VIN level error 28 GPB3 GPI gpiochip5 11 Digital input 3 (DIO circuit) I2C3 Device name: /dev/i2c-2 Signal Processor pin Default function Clock E10 I2C3_SCL Data F10 I2C3_SDA Expander F Part number:  SC16IS752IBS Expander F diagram Expander F pins description Pin Type Usage User-space name Description 1 RXA(I) RS485_UART4_RX X RS485 UART4 RX 2 RESET/ RS485_NRST X Reset 3 XTAL1(I) TXCO_OUT X Oscillator output 4 XTAL2(O) NC X Not connected 5 VDD +3V3 X Power supply 6 I2C / SPI/ GND X Ground 7 CS/ / A0 SPI2_CS2 X SPI chip select 8 SI / A1 SPI2_MOSI X SPI master out slave in 9 SO SPI2_MISO X SPI master in slave out 10 SCL / SCLK SPI2_SCLK X SPI clock 11 SDA / VSS GND X Ground 12 VSS GND X Ground 14 IRQ/ RS485_INT X RS485 interrupt 15 CTSB/ NC X Not connected 16 RTSB/ RS485_UART3_RTS X RS485 UART3 RTS 17 GPIO0 / DSRB/ NC X Not connected 18 GPIO1 / DTRB/ NC X Not connected 19 GPIO2 / CDB/ NC X Not connected 20 GPIO3 / RIB/ NC X Not connected 22 TXB(O) RS485_UART3_TX X RS485 UART3 TX 23 RXB(I) RS485_UART3_RX X RS485 UART3 RX 24 GPIO4 / DSRA/ NC X Not connected 25 GPIO5 / DTRA/ NC X Not connected 26 GPIO6 / CDA/ NC X Not connected 27 GPIO7 / RIA/ NC X Not connected 30 RTSA/ RS485_UART4_RTS X RS485 UART4 RTS 31 CTSA/ NC X Not connected 32 TXA(O) RS485_UART4_TX X RS485 UART4 TX SPI2 Signal Processor pin Default function Chip select 0 A6 SPI2_CS0 Chip select 1 AF12 SPI2_CS1 Chip select 2 AB19 SPI2_CS2 Master in slave out A8 SPI2_MISO Clock E6 SPI2_SCLK Master out slave in B8 SPI2_MOSI