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EV3 Processor

  1. Documentation
  2. Kernel Hacker's Notebook
  3. EV3 Processor

Essentials

Documentation

System Components

Used by EV3

Not used by EV3

Not sure yet

Pin Assignments

There are 400 pins on the chip. 160 of the pins are multiplexed, meaning that each pin can perform multiple functions. This is how the EV3 uses each multiplexed pin. See section 10.4.9 in the AM1808 technical reference manual to see where this came from.

This is based on the lms2012 code and hardware schematic revision J. Both are not 100% reliable representations of the mass produced hardware, so there could be inaccurate information here. You have been warned.

MUX Function Schematic Cross-
reference		 Usage
0 28 UART2 CTS CTSMCU_RTSBT Bluetooth
24 UART2 RTS RTSMCU_CTSBT Bluetooth
20 AHCLKX PRUCLK PRU clock for soft UARTs
16 AHCLKR PRUCLK PRU clock for soft UARTs
12 GPIO 0-12 DIGIC0 Input Port 3 Pin 5 I/O
8 GPIO 0-13 DIGIB1 Input Port 2 Pin 6 I/O / I2C Data
4 GPIO 0-14 DIGIB0 Input Port 2 Pin 5 I/O
0 GPIO 0-15 DIGIA1 Input Port 1 Pin 6 I/O / I2C Data
1 28 ECAP1 APWM1 MDPWM Output Port D Motor Driver
24 GPIO 0-1 DIGID0 Input Port 4 Pin 5 I/O
20 GPIO 0-2 DIGIA0 Input Port 1 Pin 5 I/O
16 GPIO 0-3 MBIN0 Output Port B Pin 2
12 GPIO 0-4 DIRA Output Port A Pin 6 In
8 GPIO 0-5 BTCLKDIS Pull down bluetooth "slow clock" signal
4 GPIO 0-6 ADCBATEN A/D Converter Battery Enable (switches battery voltage to ADC channel 4)
0 ECAP2 APWM2 BTSLOWCLK Bluetooth "slow" clock
2 28 ECAP0 APWM0 MCPWM Output Port C Motor Driver
24 AXR1 RXIND Input Port 4 Pin 6 UART RXD
20 AXR2 RXINC Input Port 3 Pin 6 UART RXD
16 AXR3/
GPIO 1-11		 TXIND Input Port 4 Pin 5 UART TXD / I2C Clock
12 AXR4/
GPIO 1-12		 TXINC Input Port 3 Pin 5 UART TXD / I2C Clock
8 GPIO 1-13 BUT1 Button 1 (Enter)
4 GPIO 1-14 DIGIC1 Input Port 3 Pin 6 I/O / I2C Data
0 GPIO 1-15 DIGID1 Input Port 4 Pin 6 I/O / I2C Data
3 28 N/C
24 SPI0 CS ADCCS SPI chip select to analog/digital converter
20 UART0 TXD/
GPIO 8-3		 TXINB Input Port 2 Pin 5 UART TXD / I2C Clock
16 UART0 RXD RXINB Input Port 2 Pin 6 UART RXD
12 SPI0 SIMO ADCMOSI
FMOSI		 SPI data from analog/digital converter
8 SPI0 SOMI ADCMISO
FMISO		 SPI data to analog/digital converter
4 EPWM0B SOUND_ARMA PWM to speaker amplifier
0 SPI0 CLK SPI0_CLK SPI Clock to analog/digital converter
4 28 UART1 TXD/
GPIO 1-0		 TXINA Input Port 1 Pin 5 UART TXD / I2C Clock
24 UART1 RXD RXINA Input Port 1 Pin 5 UART RXD
20 UART2 TXD TXMCU_RXBT Bluetooth
16 UART2 RXD RXMCU_TXBT Bluetooth
12 I2C0 SDA I2C0_SDA EEPROM I2C data
8 I2C0 SCL I2C0_SCL EEPROM I2C clock
4 SPI0 SCS0 NPCS0 Flash memory SPI chip select
0 ? PRU_CLK
5 28 GPIO 2-8 DIRD Output Port D Pin 6 In
24 GPIO 2-9 DIRB Output Port B Pin 6 In
20 SPI1 SIMO MOSIDIS LCD SPI data
16 GPIO 2-11 MISODIS LCD A0 display data/command selector
12 GPIO 2-12 CSDIS LCD chip select (active low)
8 SPI1 CLK SCKDIS LCD SPI Clock
4 EPWM1B MAPWM Output Port A Motor Driver
0 EPWM1A MBPWM Output Port A Motor Driver
6 28 GPIO 2-0 FHOLD Flash memory hold (active low)
24 GPIO 2-1 MBIN1 Output Port B Pin 1
20 GPIO 2-2 LEGDETA Input Port 1 Pin 2 In
16 N/C
12 N/C
8 GPIO 2-5 DETB0 Output Port B Pin 5 In
4 N/C
0 GPIO 2-7 N/C FIQ shadowing (*was TP4 on pre-release hardware)
7 28 GPIO 3-8 DETC0 Output Port C Pin 5 In
24 N/C
20 N/C
16 N/C
12 N/C
8 N/C
4 GPIO 3-14 DIRC Output Port C Pin 6 In
0 GPIO 3-15 MAIN0 Output Port A Pin 1
8 28 N/C
24 N/C
20 GPIO 3-2 HWID2 Hardware ID (not used)
16 GPIO 3-3 PIC_EN Bluetooth PIC enable
12 GPIO 3-4 HWID1 Hardware ID (not used)
8 GPIO 3-5 HWID0 Hardware ID (not used)
4 GPIO 3-6 MAIN1 Output Port A Pin 2
0 N/C
9 28 N/C
24 GPIO 4-9 BTnSHUTD Bluetooth enable (active low)
20 GPIO 4-10 HWID3 Hardware ID (not used)
16 N/C
12 N/C
8 N/C
4 GPIO 4-14 PIC_RST Bluetooth PIC reset
0 N/C
10 28 N/C
24 N/C
20 MMCSD0 DAT3 MCI0_DA3 SD Card Reader
16 MMCSD0 DAT2 MCI0_DA2 SD Card Reader
12 MMCSD0 DAT1 MCI0_DA1 SD Card Reader
8 MMCSD0 DAT0 MCI0_DA0 SD Card Reader
4 MMCSD0 CMD MCI0_CDA SD Card Reader
0 MMCSD0 CLK MCI0_CK SD Card Reader
11 28 GPIO 5-8 INTB0 Output Port B Pin 5 In
24 GPIO 5-9 MCIN1 Output Port C Pin 2
20 GPIO 5-10 MDIN0 Output Port D Pin 2
16 GPIO 5-11 INTA0 Output Port A Pin 5 In
12 N/C
8 GPIO 5-13 INTC0 Output Port C Pin 5 In
4 GPIO 5-14 SD_SW SD card detect switch
0 GPIO 5-15 DETD0 Output Port D Pin 5 In
12 28 GPIO 5-0 RSTDIS LCD reset (active low)
24 N/C
20 GPIO 5-2 FWP Flash memory write protection (active low)
16 GPIO 5-3 MDIN1 Output Port D Pin 1
12 GPIO 5-4 DETA0 Output Port A Pin 1 In
8 N/C
4 N/C
0 GPIO 5-7 CTS_PIC Bluetooth CTS
13 28 GPIO 6-8 MCIN0 Output Port C Pin 1
24 GPIO 6-9 INTD0 Output Port D Pin 5 In
20 GPIO 6-10 BUT5 Button 5 (Back)
16 GPIO 6-11 5VPENON System 5V Power (used to turn off EV3)
12 GPIO 6-12 DIODE3 LED 3 (right, red)
8 GPIO 6-13 DIODE0 LED 0 (left, red)
4 GPIO 6-14 DIODE2 LED 2 (right, green)
0 GPIO 6-15 SOUNDEN Speaker amplifier enable
14 28 N/C
24 N/C
20 N/C
16 N/C
12 N/C
8 N/C
4 GPIO 6-6 BUT4 Button 4 (left)
0 GPIO 6-7 DIODE1 LED 1 (left, green)
15 28 N/C
24 N/C
20 N/C
16 N/C
12 N/C
8 N/C
4 N/C
0 N/C
16 28 GPIO 7-10 RXIND_EN
TXIND_EN		 Input Port 4 buffer enable (active low)
24 GPIO 7-11 LEGDETC Input Port 3 Pin 2 In
20 GPIO 7-12 BUT3 Button 3 (right)
16 N/C
12 GPIO 7-14 BUT2 Button 2 (down)
8 GPIO 7-15 BUT0 Button 0 (up)
4 GPIO 6-5 P_EN System power enable
0 N/C
17 28 BOOT2 BOOT2 Select boot device
24 BOOT3 BOOT3 Select boot device
20 BOOT4 BOOT4 Select boot device
16 BOOT5 BOOT5 Select boot device
12 BOOT6 BOOT6 Select boot device
8 BOOT7 BOOT7 Select boot device
4 GPIO 7-8 LEGDETD Input Port 4 Pin 2 In
0 GPIO 7-9 RXINC_EN
TXINC_EN		 Input Port 3 buffer enable (active low)
18 28 GPIO 8-10 I_ONA Input Port 1 Pin 1 Out
24 GPIO 8-11 RXINA_EN
TXINA_EN		 Input Port 1 buffer enable (active low)
20 GPIO 8-12 I_ONB Input Port 2 Pin 1 Out
16 N/C
12 GPIO 8-14 RXINB_EN
TXINB_EN		 Input Port 2 buffer enable (active low)
8 GPIO 8-15 LEGDETB Input Port 2 Pin 2 In
4 BOOT0 BOOT0 Select boot device
0 BOOT1 BOOT1 Select boot device
19 28 RTCK RTCK1 Realtime clock output
24 N/C
20 N/C
16 GPIO 6-2 ADCACK Analog/Digital converter GPIO0
12 GPIO 6-3 OC5V USB1 overcurrent
8 GPIO 6-4 I_OND Input Port 4 Pin 1 Out
4 GPIO 8-8 SW_RECHARGE Rechargeable battery indicator
0 GPIO 8-9 I_ONC Input Port 3 Pin 1 Out