MT3620 Support Status

This document describes the current status of Azure Sphere support for the MediaTek MT3620. You may also want to refer to the MT3620 Product Brief, which is available for download on the MediaTek MT3620 web page. In addition, MediaTek produces the MT3620 Hardware User Guide, which is a detailed guide to integrating the MT3620 MCU into your own hardware.

Important

In the context of this document, not currently supported means that customer use of the feature is restricted at the current time, and this restriction is likely to be removed in the future. Conversely, not accessible means that the feature cannot be used by customers, and this restriction is unlikely to change.

If you have feature requests or feedback, we welcome your comments on the Azure Sphere community forum.

MT3620 block diagram

The block diagram shows the support provided for each MT3620 component. The sections that follow the diagram provide additional details about these components.

MT3620 block diagram showing supported features

I/O peripherals

The MT3620 design includes a total of 76 programmable I/O pins. As shown in the following two tables, most of the pins are multiplexed between general-purpose I/O (GPIO) and other functions. In addition to the GPIO pins listed, GPIO12-23 are available on MT3620 pins 27-38 respectively.

table showing mt3620 i/o peripheral pinout (ADC, I2S, PWM)

Referring to the following table, pins marked "UNUSED" are not used by the associated ISU peripheral and can be configured for use as GPIO pins.

Note

Once an ISU peripheral has been allocated to a core, all 5 ISU pins, including unused pins, are restricted to use in that core.

table showing mt3620 i/o peripheral pinout (ISU)

GPIO/PWM/counters

Some pins are multiplexed between GPIO, pulse width modulation (PWM), and hardware counters.

GPIO functions currently supported are setting output high/low and reading input. Open drain/open source driving modes and control of drive strength are also supported. External Interrupts are supported on the M4 core but not on the A7 core.

The MT3620 has 12 PWM channels, identified by PWM0-PWM11. They are organized into 3 groups of 4 channels. Each group is associated with a PWM controller (PWM-CONTROLLER-0, PWM-CONTROLLER-1, PWM-CONTROLLER-2). The PWM channels and GPIO pins GPIO0 through GPIO11 map to the same pins on the MT3620. If your application uses a PWM controller, all of the pins associated with that controller are allocated for use as PWM outputs and none of them can be used for GPIO.

The PWM hardware can be configured to use one of three fixed-clock frequencies: 32 KHz, 2 MHz (XTAL/13), or 26 MHz (XTAL). On the real-time (RT) cores, a real-time application (RTApp) can select which clock to use as the base. On the high-level core (A7), the Linux driver will always use the 2 MHz clock. This results in duty cycle and period limitations in high-level applications, as explained in Use PWMs in high-level applications.

Serial interface (ISU) blocks

The MT3620 design includes five serial interface blocks, each of which contains five pins. (These blocks are also called ISU, for "I2C, SPI, UART.") These serial interface blocks can multiplex GPIO, universal asynchronous receiver-transmitter (UART), inter-integrated circuit (I2C) and serial peripheral interface (SPI).

UART is supported at 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800, 500000, 576000, 921600, 1000000, 1152000, 1500000, and 2000000 baud. There is a 32-byte hardware receive buffer. The following UART settings are supported, with 8N1 (8 data bits, 1 stop bit, and no parity) as the default setting:

  • Data bit: 5, 6, 7, and 8.
  • Stop bit: 1 and 2.
  • Parity: odd, even, and none.
  • Flow control mode: RTS/CTS, XON/XOFF, and no flow control.

SPI transactions are supported up to 40 MHz. You can connect up to two subordinate SPI devices to each ISU. When you use an ISU port as an SPI master interface, you can't use the same port as an I2C or UART interface. Simultaneous bidirectional read and write (full-duplex) SPI operations within a single bus transaction are not supported. The following SPI settings are supported:

  • Communication mode (clock polarity, clock phase): SPI mode 0 (CPOL = 0, CPHA = 0), SPI mode 1 (CPOL = 0, CPHA = 1), SPI mode 2 (CPOL = 1, CPHA = 0), and SPI mode 3 (CPOL = 1, CPHA = 1).
  • Bit order: least significant is sent first, and most significant is sent first.
  • Chip select polarity: active-high, active-low. Active-low is the default setting.

7-bit subordinate device addresses are supported for I2C. 8-bit or 10-bit I2C subordinate addresses are not supported. When you use an ISU port as an I2C master interface, you can't use the same port as an SPI or UART interface. 0-byte I2C reads are not supported. The following I2C settings are supported:

  • 100 KHz, 400 KHz, and 1 MHz bus speeds.
  • Custom timeout for operations.

I2S

Two blocks of five pins are multiplexed between GPIO and I2S. I2S is currently supported for M4 applications only.

ADC

The MT3620 contains a 12-bit ADC with 8 input channels. A block of eight pins is multiplexed between GPIO and the ADC. The ADC input channels and the GPIO pins GPIO41 through GPIO48 map to the same pins on the MT3260. However, if your application uses the ADC, then all 8 pins are allocated for use as ADC inputs and none of them can be used for GPIO.

ARM Cortex-M4F subsystems

The MT3620 includes two general-purpose ARM Cortex-M4F subsystems, each of which has a dedicated GPIO/UART block.

The MT3620 supports a default clock rate of 26 MHz. However, each M4 core can be independently configured to run at any clock rate between 1 MHz and 200 MHz by setting its HCLK_CK_CTRL register. The following code demonstrates one way to set the clock rate to 200 MHz:

        volatile unsigned int *hclk_ck_ctrl = (unsigned int *)0x2101000c;

        *hclk_ck_ctrl = 0x00040200;

Note

For details about programming the M4 cores on the MT3620, see the MT3620 documentation published by MediaTek. If the datasheet does not contain all the information you need, please email Avnet (Azure.Sphere@avnet.com) to request the full datasheet.

The ARM Cortex-M4F subsystems can be programmed to support external interrupts. See Use external interrupts in real-time capable applications for details.

Application processor subsystem

The ARM Cortex-A7 subsystem runs a customer application along with the Microsoft-supplied Linux-based kernel, services, and libraries.

The service UART is dedicated to system functionality for the A7 subsystem. It is not available for customer application use.

The one-time programmable e-fuse block, for storing device specific information, cannot be used by customer applications.

Wi-Fi Subsystem

The Wi-Fi subsystem is currently IEEE 802.11 b/g/n compliant at both 2.4 GHz and 5 GHz.

Currently, Azure Sphere only supports WPA2, EAP-TLS, and open (no password) authentication.

See RF test tools for information about radio-frequency testing and calibration.

Power control

The MT3620 includes Power Down and Power Profile features to control power consumption. See Power Down considerations and Power Profile considerations for details.

Clocks and power sources

The main crystal can currently only be 26MHz. Crystal frequencies other than 26MHz are not currently supported in software.

Brownout detection

Brownout detection is not currently supported.

Hardware watchdog timers

The MTK3620 includes several watchdog timers:

  • One watchdog timer dedicated for use by the Pluton security domain. This watchdog timer is not available for use by applications.
  • One watchdog timer available to the application processor. The Azure Sphere OS uses this watchdog timer for system services. This watchdog timer is not available to applications.
  • A watchdog timer for each of the real-time cores. These watchdog timers are available to real-time applications.

See Use a watchdog timer in an RTApp for more information.

SWD, SWO

Serial-wire debug (SWD, pins 98-99) is supported for M4 applications only. Serial-wire output (SWO, pin 100) is not currently supported. Debugging an A7 application is supported by a Microsoft-supplied gdb-based mechanism.

RAM and flash

The MT3620 includes approximately 5 MB RAM on-die, including 256 KiB in each I/O subsystem and 4 MB in the A7 application subsystem.

The MT3620 can be ordered with 16 MB of SPI flash memory.

For information about RAM and flash available for applications, see Memory available for applications.

Manufacturing test support

Documentation and utilities to support the integration of custom manufacturing test applications with factory processes are not yet available.

Pinout

Pin# Pin Name Major Functions Type Description Comments
1 GND P Ground
2 AVDD_3V3_WF_A_PA PI 3.3V power rail for 5GHz Wi-Fi power amplifier
3 AVDD_3V3_WF_A_PA PI 3.3V power rail for 5GHz Wi-Fi power amplifier
4 NC
5 NC
6 AVDD_1V6_WF_TRX PI 1.6V power rail for Wi-Fi transmit/receive
7 AVDD_1V6_WF_AFE PI 1.6V power rail for Wi-Fi analog front end
8 NC
9 AVDD_1V6_XO PI 1.6V power rail for main crystal oscillator
10 MAIN_XIN AI Main crystal oscillator input
11 WF_ANTSEL0 DO Wi-Fi antenna select for external DPDT switch
12 WF_ANTSEL1 DO Wi-Fi antenna select for external DPDT switch
13 GPIO0 GPIO0/PWM0 DIO Interrupt-capable GPIO multiplexed with PWM output
14 GPIO1 GPIO1/PWM1 DIO Interrupt-capable GPIO multiplexed with PWM output
15 GPIO2 GPIO2/PWM2 DIO Interrupt-capable GPIO multiplexed with PWM output
16 GPIO3 GPIO3/PWM3 DIO Interrupt-capable GPIO multiplexed with PWM output
17 GPIO4 GPIO4/PWM4 DIO Interrupt-capable GPIO multiplexed with PWM output
18 GPIO5 GPIO5/PWM5 DIO Interrupt-capable GPIO multiplexed with PWM output
19 GPIO6 GPIO6/PWM6 DIO Interrupt-capable GPIO multiplexed with PWM output
20 GPIO7 GPIO7/PWM7 DIO Interrupt-capable GPIO multiplexed with PWM output
21 GPIO8 GPIO8/PWM8 DIO Interrupt-capable GPIO multiplexed with PWM output
22 GPIO9 GPIO9/PWM9 DIO Interrupt-capable GPIO multiplexed with PWM output
23 DVDD_1V15 PI 1.15V power rail
24 DVDD_3V3 PI 3.3V power rail
25 GPIO10 GPIO10/PWM10 DIO Interrupt-capable GPIO multiplexed with PWM output
26 GPIO11 GPIO11/PWM11 DIO Interrupt-capable GPIO multiplexed with PWM output
27 GPIO12 DIO Interrupt-capable GPIO Interrupts are not currently supported
28 GPIO13 DIO Interrupt-capable GPIO Interrupts are not currently supported
29 GPIO14 DIO Interrupt-capable GPIO Interrupts are not currently supported
30 GPIO15 DIO Interrupt-capable GPIO Interrupts are not currently supported
31 GPIO16 DIO Interrupt-capable GPIO Interrupts are not currently supported
32 GPIO17 DIO Interrupt-capable GPIO Interrupts are not currently supported
33 GPIO18 DIO Interrupt-capable GPIO Interrupts are not currently supported
34 GPIO19 DIO Interrupt-capable GPIO Interrupts are not currently supported
35 GPIO20 DIO Interrupt-capable GPIO Interrupts are not currently supported
36 GPIO21 DIO Interrupt-capable GPIO Interrupts are not currently supported
37 GPIO22 DIO Interrupt-capable GPIO Interrupts are not currently supported
38 GPIO23 DIO Interrupt-capable GPIO Interrupts are not currently supported
39 GPIO26 GPIO26/ SCLK0/TXD0 DIO GPIO multiplexed with ISU 0 functions
40 GPIO27 GPIO27/ MOSI0/RTS0/SCL0 DIO GPIO multiplexed with ISU 0 functions
41 GND P Ground
42 GPIO28 GPIO28/ MISO0/RXD0/SDA0 DIO GPIO multiplexed with ISU 0 functions
43 GPIO29 GPIO29/CSA0/CTS0 DIO GPIO multiplexed with ISU 0 functions
44 DVDD_1V15 PI 1.15V power rail
45 GPIO30 GPIO30/CSB0 DIO GPIO multiplexed with ISU 0 functions
46 GPIO31 GPIO31/ SCLK1/TXD1 DIO GPIO multiplexed with ISU 1 functions
47 GPIO32 GPIO32/ MOSI1/RTS1/SCL1 DIO GPIO multiplexed with ISU 1 functions
48 GPIO33 GPIO33/ MISO1/RXD1/SDA1 DIO GPIO multiplexed with ISU 1 functions
49 GPIO34 GPIO34/CSA1/CTS1 DIO GPIO multiplexed with ISU 1 functions
50 GPIO35 GPIO35/CSB1 DIO GPIO multiplexed with ISU 1 functions
51 GPIO36 GPIO36/ SCLK2/TXD2 DIO GPIO multiplexed with ISU 2 functions
52 GPIO37 GPIO37/ MOSI2/RTS2/SCL2 DIO GPIO multiplexed with ISU 2 functions
53 GPIO38 GPIO38/ MISO2/RXD2/SDA2 DIO GPIO multiplexed with ISU 2 functions
54 GPIO39 GPIO39/CSA2/CTS2 DIO GPIO multiplexed with ISU 2 functions
55 GPIO40 GPIO40/CSB2 DIO GPIO multiplexed with ISU 2 functions
56 DVDD_3V3 PI 3.3V power rail
57 DVDD_1V15 PI 1.15V power rail
58 GPIO41 GPIO41/ADC0 DIO GPIO multiplexed with ADC input
59 GPIO42 GPIO42/ADC1 DIO GPIO multiplexed with ADC input
60 GPIO43 GPIO43/ADC2 DIO GPIO multiplexed with ADC input
61 GPIO44 GPIO44/ADC3 DIO GPIO multiplexed with ADC input
62 GPIO45 GPIO45/ADC4 DIO GPIO multiplexed with ADC input
63 GPIO46 GPIO46/ADC5 DIO GPIO multiplexed with ADC input
64 GPIO47 GPIO47/ADC6 DIO GPIO multiplexed with ADC input
65 GPIO48 GPIO48/ADC7 DIO GPIO multiplexed with ADC input
66 AVDD_2V5_ADC PI 2.5V power rail for ADC
67 VREF_ADC AI Reference voltage for ADC
68 AVSS_2V5_ADC P Ground for ADC
69 EXT_PMU_EN DO External power supply enable output
70 WAKEUP DI External wakeup from deepest sleep mode Not currently supported
71 AVDD_3V3_RTC PI 3.3V power rail for real-time clock
72 RTC_XIN AI Realtime clock crystal oscillator input
73 RTC_XOUT AO Realtime clock crystal oscillator output
74 AVDD_3V3_XPPLL PI 3.3V power rail for internal phase-locked loop
75 I2S_MCLK0_ALT AO Analog alternative to MCLK0 I2S is currently supported for M4 applications only.
76 I2S_MCLK1_ALT AO Analog alternative to MCLK1 I2S is currently supported for M4 applications only.
77 DVDD_1V15 PI 1.15V power rail
78 DVDD_1V15 PI 1.15V power rail
79 VOUT_2V5 PO Output from internal 2.5V LDO
80 AVDD_3V3 PI 3.3V power rail
81 PMU_EN DI Internal PMU override
82 RESERVED
83 GND P Ground
84 SENSE_1V15 AI Sense input to stabilise the 1.15V power supply
85 VOUT_1V15 PO Output from internal 1.15V LDO
86 AVDD_1V6_CLDO PI 1.6V power rail for the internal 1.15V core LDO
87 PMU_CAP A Connect a capacitor between this pin and AVDD_3V3_BUCK to maintain PMU stability
88 AVDD_3V3_BUCK PI 3.3V power rail for internal 1.6V buck DC-DC converter
89 AVDD_3V3_BUCK PI 3.3V power rail for internal 1.6V buck DC-DC converter
90 VOUT_1V6 PO Output from internal 1.6V buck converter
91 VOUT_1V6 PO Output from internal 1.6V buck converter
92 AVSS_3V3_BUCK P Ground for internal 1.6V buck converter
93 AVSS_3V3_BUCK P Ground for internal 1.6V buck converter
94 DEBUG_RXD DI Reserved for Azure Sphere debug
95 DEBUG_TXD DO Reserved for Azure Sphere debug
96 DEBUG_RTS DO Reserved for Azure Sphere debug
97 DEBUG_CTS DI Reserved for Azure Sphere debug
98 SWD_DIO DIO ARM SWD for Cortex-M4F debug
99 SWD_CLK DI ARM SWD for Cortex-M4F debug
100 SWO DO ARM SWO for Cortex-M4F debug Not currently supported
101 GPIO56 GPIO56/TX0 DIO GPIO multiplexed with I2S 0 I2S is currently supported for M4 applications only.
102 GPIO57 GPIO57 /MCLK0 DIO GPIO multiplexed with I2S 0 I2S is currently supported for M4 applications only.
103 GPIO58 GPIO58/FS0 DIO GPIO multiplexed with I2S 0 I2S is currently supported for M4 applications only.
104 GPIO59 GPIO59/RX0 DIO GPIO multiplexed with I2S 0 I2S is currently supported for M4 applications only.
105 GPIO60 GPIO60/ BCLK0 DIO GPIO multiplexed with I2S 0 I2S is currently supported for M4 applications only.
106 DVDD_1V15 PI 1.15V power rail
107 DVDD_3V3 PI 3.3V power rail
108 GPIO61 GPIO61/TX1 DIO GPIO multiplexed with I2S 1 I2S is currently supported for M4 applications only.
109 GPIO62 GPIO62/ MCLK1 DIO GPIO multiplexed with I2S 1 I2S is currently supported for M4 applications only.
110 GPIO63 GPIO63/FS1 DIO GPIO multiplexed with I2S 1 I2S is currently supported for M4 applications only.
111 GPIO64 GPIO64/RX1 DIO GPIO multiplexed with I2S 1 I2S is currently supported for M4 applications only.
112 GPIO65 GPIO65/ BCLK1 DIO GPIO multiplexed with I2S 1 I2S is currently supported for M4 applications only.
113 GPIO66 GPIO66/ SCLK3/TXD3 DIO GPIO multiplexed with ISU 3 functions
114 GPIO67 GPIO67/ MOSI3/RTS3/SCL3 DIO GPIO multiplexed with ISU 3 functions
115 GPIO68 GPIO68/ MISO3/RXD3/SDA3 DIO GPIO multiplexed with ISU 3 functions
116 GPIO69 GPIO69/CSA3/CTS3 DIO GPIO multiplexed with ISU 3 functions
117 GPIO70 GPIO70/CSB3 DIO GPIO multiplexed with ISU 3 functions Currently supports GPIO only
118 DVDD_3V3 PI 3.3V power rail
119 GPIO71 GPIO71/ SCLK4/TXD4 DIO GPIO multiplexed with ISU 4 functions
120 GPIO72 GPIO72/ MOSI4/RTS4/SCL4 DIO GPIO multiplexed with ISU 4 functions
121 DVDD_1V15 PI 1.15V power rail
122 GPIO73 GPIO73/ MISO4/RXD4/SDA4 DIO GPIO multiplexed with ISU 4 functions
123 GPIO74 GPIO74/CSA4/CTS4 DIO GPIO multiplexed with ISU 4 functions
124 GPIO75 GPIO75/CSB4 DIO GPIO multiplexed with ISU 4 functions
125 SYSRST_N DI System reset, active low
126 DVDD_1V15 PI 1.15V power rail
127 SERVICE_TXD DO Azure Sphere service port Not available for customer application use
128 SERVICE_RTS DO Azure Sphere service port Not available for customer application use
129 SERVICE_RXD DI Azure Sphere service port Not available for customer application use
130 SERVICE_CTS DI Azure Sphere service port Not available for customer application use
131 RESERVED
132 DVDD_1V15 PI 1.15V power rail
133 DVDD_3V3 PI 3.3V power rail
134 RECOVERY_RXD DI Azure Sphere recovery port Not available for customer application use
135 RECOVERY_TXD DO Azure Sphere recovery port Not available for customer application use
136 RECOVERY_RTS DO Azure Sphere recovery port Not available for customer application use
137 RECOVERY_CTS DI Azure Sphere recovery port Not available for customer application use
138 IO0_GPIO85 IO0_GPIO85/ IO0_RXD DI Dedicated GPIO multiplexed with UART for I/O M4 0
139 IO0_GPIO86 IO0_GPIO86/ IO0_TXD DO Dedicated GPIO multiplexed with UART for I/O M4 0
140 IO0_GPIO87 IO0_GPIO87/ IO0_RTS DO Dedicated GPIO multiplexed with UART for I/O M4 0
141 IO0_GPIO88 IO0_GPIO88/ IO0_CTS DI Dedicated GPIO multiplexed with UART for I/O M4 0
142 IO1_GPIO89 IO1_GPIO89/ IO1_RXD DI Dedicated GPIO multiplexed with UART for I/O M4 1
143 IO1_GPIO90 IO1_GPIO90/ IO1_TXD DO Dedicated GPIO multiplexed with UART for I/O M4 1
144 DVDD_3V3 PI 3.3V power rail
145 IO1_GPIO91 IO1_GPIO91/ IO1_RTS DO Dedicated GPIO multiplexed with UART for I/O M4 1
146 IO1_GPIO92 IO1_GPIO92/ IO1_CTS DI Dedicated GPIO multiplexed with UART for I/O M4 1
147 RESERVED
148 TEST DI Must be pulled low for normal operation
149 WF_G_RF_AUXIN RF 2.4GHz Wi-Fi receive diversity port
150 NC
151 AVDD_3V3_WF_G_PA PI 3.3V power rail for 2.4GHz Wi-Fi power amplifier
152 NC
153 WF_G_RF_ION RF 2.4GHz Wi-Fi antenna port (differential)
154 WF_G_RF_ION RF 2.4GHz Wi-Fi antenna port (differential)
155 WF_G_RF_IOP RF 2.4GHz Wi-Fi antenna port (differential)
156 WF_G_RF_IOP RF 2.4GHz Wi-Fi antenna port (differential)
157 NC
158 AVDD_3V3_WF_G_TX PI 3.3V power rail for 2.4GHz Wi-Fi power transmit
159 WF_A_RF_AUXIN RF 5GHz Wi-Fi receive diversity port
160 AVDD_3V3_WF_A_TX PI 3.3V power rail for 5GHz Wi-Fi power transmit
161 NC
162 WF_A_RFIO RF 5GHz Wi-Fi antenna port (unbalanced)
163 WF_A_RFIO RF 5GHz Wi-Fi antenna port (unbalanced)
164 GND P Ground
165 EPAD P Ground