3.4.2 mikroBUS Interface

The SAM9X75-Curiosity board hosts a mikroBUS socket (J25) with PTA (Packet Traffic Arbitration) connector for wireless communications (J26). The mikroBUS standard defines the main board sockets and add-on boards used for interfacing the microprocessor with integrated modules having a proprietary pin configuration. For details, refer to the mikroBUS documentation on www.mikroe.com/mikrobus.

The following figure shows the mikroBUS interface.

Figure 3-24. mikroBUS Interface

The following table shows the mikroBUS connector signal description.

Table 3-10. mikroBUS Connector Signal Description
Pin No. PIO Signal Name Signal Description
1 PA31 MBUS_1_AN_PA31 Analog
2 NRST or PA17 NRST or NRST_OUT_PC25 Reset
3 PC24 MBUS_1_SPI_NPCS_PC24 SPI Chip Select
4 PC26 MBUS_1_SPI_SCK_PC26 SPI Clock
5 PC23 MBUS_1_SPI_MISO_PC23 SPI MISO
6 PC22 MBUS_1_SPI_MOSI_PC22 SPI MOSI
7 – VDD_3V3 3.3V
8 – GND GND
9 – GND GND
10 – 5V_MAIN 5V
11 PC0 MBUS_1_I2C_DATA_PC0 TWI Data
12 PC1 MBUS_1_I2C_CLK_PC1 TWI Clock
13 PA28 MBUS_1_TX_PA28 UART Transmit
14 PA29 MBUS_1_RX_PA29 UART Receive
15 PB18 MBUS_1_INT_PB18 Interrupt
16 PC21 MBUS_1_PWM_PC21 Pulse Width Modulated

The SAM9X75-Curiosity board can embed several radio solutions using the 2.4 GHz radio bandwidth with Wi-Fi and Bluetooth solutions. The coexistence between the radio modules is necessary to ensure a good packet transfer rate and pass RED and FCC certifications. The PTA interface between the modules consists of a set of 3-wire signals and organizes wireless packet traffic for communication protocols operating in the same frequency band without affecting RF performance by intelligently sharing the frequency band.

The following figure shows the mikroBUS PTA interface for Wireless.

Figure 3-25. mikroBUS PTA for Wireless Connector
A blue and red line with a white background Description automatically generated with medium confidence

The following table shows the mikroBUS PTA for Wireless connector signal description.

Table 3-11. mikroBUS PTA for Wireless Connector Signal Description
Pin No. PIO Signal Name Signal Description
1 – MBUS_1_COEX_PTA_BT-ACTIVE PTA Bluetooth Active Input
2 – MBUS_1_COEX_PTA_BT-PRIORITY PTA Bluetooth Priority Input
3 – MBUS_1_COEX_PTA_BT-WLAN-ACTIVE PTA Wireless LAN Active Output
4 – GND Ground