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.

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

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