Xplained Pro Standard Extension Headers

The SAM4L8 Xplained Pro headers EXT1, EXT2, EXT3, and EXT4 offers access to the I/O of the microcontroller in order to expand the board e.g. by connecting extensions to the board. These headers all comply with the standard Xplained Pro extension header specification. All headers have a pitch of 2.54mm.

Table 1. Extension Header EXT1
Pin on EXT1 SAM4L8 pin Function Shared functionality
1 - - Communication line to ID chip on extension board
2 - - GND
3 PA04 ADCIFE/AD[0]  
4 PA05 ADCIFE/AD[1]  
5 PB12 GPIO LCD connector (EXT5)
6 PC02 GPIO  
7 PC00 TC/1/A0  
8 PC01 TC/1/B0  
9 PC25 EIC/EXTINT[2] LCD connector (EXT5)
10 PB13 SPI/NPCS[1] LCD connector (EXT5)
11 PA23 TWIMS/0/TWD LCD connector (EXT5)
12 PA24 TWIMS/0/TWCK LCD connector (EXT5)
13 PB00 USART/0/RXD EXT4
14 PB01 USART/0/TXD EXT4
15 PC03 SPI/NPCS[0]  
16 PA22 SPI/MOSI EXT2 and LCD connector (EXT5)
17 PA21 SPI/MISO EXT2 and LCD connector (EXT5)
18 PC30 SPI/SCK EXT2 and LCD connector (EXT5)
19 - - GND
20 - - VCC
Table 2. Extension Header EXT2
Pin on EXT2 SAM4L8 pin Function Shared functionality
1 - - Communication line to ID chip on extension board
2 - - GND
3 PA07 ADCIFE/AD[2]  
4 PB02 ADCIFE/AD[3]  
5 PC08 GPIO  
6 PB10 GPIO LCD connector (EXT5)
7 PC04 TC/1/A2  
8 PC05 TC/1/B2 LCD connector (EXT5)
9 PC06 EIC/EXTINT[8]  
10 PC09 GPIO  
11 PB14 TWIMS/3/TWD EXT3, EXT4, and LCD connector (EXT5)
12 PB15 TWIMS/3/TWCK EXT3, EXT4, and LCD connector (EXT5)
13 PC26 USART/1/RXD EXT3 and LCD connector (EXT5)
14 PC27 USART/1/TXD EXT3 and LCD connector (EXT5)
15 PB11 SPI/NPCS[2] LCD connector (EXT5)
16 PA22 SPI/MOSI EXT1 and LCD connector (EXT5)
17 PA21 SPI/MISO EXT1 and LCD connector (EXT5)
18 PC30 SPI/SCK EXT1 and LCD connector (EXT5)
19 - - GND
20 - - VCC
Table 3. Extension Header EXT3
Pin on EXT3 SAM4L8 pin Function Shared functionality
1 - - Communication line to ID chip on extension board
2 - - GND
3 PB03 ADCIFE/AD[4]  
4 PB04 ADCIFE/AD[5]  
5 PC15 GPIO LCD connector (EXT5)
6 PC16 GPIO LCD connector (EXT5)
7 PA08 TC/0/A0 LCD connector (EXT5)
8 PA09 TC/0/B0 LCD connector (EXT5)
9 PA06 EIC/EXTINT[1]  
10 PA10 GPIO LCD connector (EXT5)
11 PB14 TWIMS/3/TWD EXT2, EXT4, and LCD connector (EXT5)
12 PB15 TWIMS/3/TWCK EXT2, EXT4, and LCD connector (EXT5)
13 PC26 USART/1/RXD EXT2 and LCD connector (EXT5)
14 PC27 USART/1/TXD EXT2 and LCD connector (EXT5)
15 PA17 GPIO LCD connector (EXT5)
16 PA20 UART/2/TXD EXT4 and LCD connector (EXT5)
17 PA19 UART/2/RXD EXT4 and LCD connector (EXT5)
18 PA18 UART/2/CLK EXT4 and LCD connector (EXT5)
19 - - GND
20 - - VCC
Table 4. Extension Header EXT4
Pin on EXT4 SAM4L8 pin Function Shared functionality
1 - - Communication line to ID chip on extension board
2 - - GND
3 PB05 ADCIFE/AD[6]  
4 PC10 ADCIFE/AD[7] USB_ID
5 PC17 GPIO LCD connector (EXT5)
6 PC18 GPIO LCD connector (EXT5)
7 PA12 TC/0/A2 LCD connector (EXT5)
8 PA13 TC/0/B2 LCD connector (EXT5)
9 PA16 GPIO LCD connector (EXT5)
10 PA15 GPIO LCD connector (EXT5)
11 PB14 TWIMS/3/TWD EXT2, EXT3, and LCD connector (EXT5)
12 PB15 TWIMS/3/TWCK EXT2, EXT3, and LCD connector (EXT5)
13 PB00 USART/0/RXD EXT1
14 PB01 USART/0/TXD EXT1
15 PA11 GPIO LCD connector (EXT5)
16 PA20 UART/2/TXD EXT3 and LCD connector (EXT5)
17 PA19 UART/2/RXD EXT3 and LCD connector (EXT5)
18 PA18 UART/2/CLK EXT3 and LCD connector (EXT5)
19 - - GND
20 - - VCC