5.1V 5.0V 3.2V
VBUS VSYS 3V3
J1 [40] [39] [36]
+---+ | | +------------+ |
| [1]-----+----------+----[D1]----+-------|5,8 1,10|-----+
| [2]--USB-DM (TP2) | | | |
| [3]--USB-DP (TP3) R10 R2 | U2 |
| [4] | | | |
| [5]--GND +-- GPIO24 +-------+6 3,9,11|--+
+---+ | | +------------+ |
R1 [37] GND
| 3V3_EN
GND 4.9V
+-----| USB |-----+
UART-0 TX | I2C-0 SDA | SPI-0 RX | GP0 [ 1] J1 [40] VBUS
UART-0 RX | I2C-0 SCL | SPI-0 CSn | GP1 [ 2] [39] VSYS
GND [ 3] [38] GND
I2C-1 SDA | SPI-0 SCK | GP2 [ 4] [37] 3V3_EN
I2C-2 SCL | SPI-0 TX | GP3 [ 5] [36] 3V3_OUT
UART-1 TX | I2C-0 SDA | SPI-0 RX | GP4 [ 6] [35] | ADC-VREF
UART-2 RX | I2C-0 SCL | SPI-0 CSn | GP5 [ 7] [34] GP28 | ADC-2
GND [ 8] [33] GND | AGND
I2C-1 SDA | SPI-0 SCK | GP6 [ 9] [32] GP27 | ADC-1 | I2C-1 SCL
I2C-1 SCL | SPI-0 TX | GP7 [10] [31] GP26 | ADC-0 | I2C-1 SDA
UART-1 TX | I2C-0 SDA | SPI-1 RX | GP8 [11] [30] RUN
UART-2 RX | I2C-0 SCL | SPI-1 CSn | GP9 [12] [29] GP22
| GND [13] [28] GND
I2C-1 SDA | SPI-1 SCK | GP10 [14] [27] GP21 | | I2C-0 SCL
I2C-1 SCL | SPI-1 TX | GP11 [15] [26] GP20 | | I2C-0 SDA
UART-0 TX | I2C-0 SDA | SPI-1 RX | GP12 [16] [25] GP19 | SPI-0 TX | I2C-1 SCL
UART-0 RX | I2C-0 SCL | SPI-1 CSn | GP13 [17] [24] GP18 | SPI-0 SCK | I2C-1 SDA
GND [18] [23] GND
I2C-1 SDA | SPI-1 SCK | GP14 [19] debug [22] GP17 | SPI-0 CSn | I2C-0 SCL | UART-1 RX
I2C-1 SCL | SPI-1 TX | GP15 [20] [-][-][-] [21] GP16 | SPI-0 RX | I2C-0 SDA | UART-0 TX
S G S
W N W
C D D
L I
K O
Optoisolated input circuit
+----------------------------------[20] GP15
| +-------------resistor-----[36] 3V3_OUT
| |
emitter | | collector
+--[D]-----[+]--+
| ^ |
| window | ITR8102 top view
| ^ |
+--[+]-----[E]--+
anode | | cathode
| +----------|>---resistor--- GND
| o LED
--| button
| o
|
+---------------------------------- 5.1V