network

This module is used to initialize various network card drivers. The network card has these function: connecting routes, disconnecting routes, viewing network card connection information, checking whether connections are made.

Please make sure the antenna is connected before using WiFi.

1.1. esp8285

Some development boards expose an AT network interface module, such as an esp8285 interface connected to the k210 processor via a serial port.

Pin 8 is the enable pin. Instantiate a GPIO object set it high to enable, low to disable. To reset, set it low, wait a short while, then set it high.

Sample code [wifi_ap_scan.py] (https://github.com/sipeed/MaixPy_scripts/blob/master/network/demo_wifi_ap_scan.py)

1.2. esp32

There is currently a esp32 module in the MaixDuino development board connected to k210 via SPI. There is also a separate TF plug-in module.

ESP8285_Module

1. network.ESP8285(uart)

Instantiate an ESP8285 NIC object, passing in an uart object. On the dock and GO currently supported by MaixPy, use the AT command module as WiFi. So the uart object is the object that communicates with the AT module, you can view the uart module routine.

Calling this method will initialize ESP8285, throwing an exception if it fails.

1.1. Parameters

• uart: UART object that communicates with the AT module

1.2. Return Value

• ESP8285: NIC object

2. ESP8285

2.1. connect(ssid, key)

Connect to a hotspot (AP/router).

Parameters

• ssid: hotspot SSID
• key: password for hotspot

Return Value

None. An exception will be thrown if an error occurs.

2.2. 2.2. ifconfig

Display the current WiFi connection information. Currently, the network does not support setting the network card configuration.

nic.ifconfig()

Parameters

None

Return Value

tuple type, the elements are all strings: (ip, netmask, gateway, dns_server, dhcp_server, mac, ssid), if not queried or invalid, the value is `"0".

2.3. isconnected

Check if WiFi is connected.

nic.isconnected()

Parameters

None

Return Value

True: Already connected False: Disconnected

2.4. disconnect

Disconnect WiFi.

Parameters

None

Return Value

None

2.5. scan

Scan for surrounding WiFi hotspots.

Parameters

None

Return Value

A list object, each element containing a string, the string comes from the response of the AT module, the content is the same as described in esp8285 AT directive document, as follows: '<ecn>,<ssid>,<rssi>,<mac>,<channel>,<freq offset>,<freq cali>,<pairwise_cipher>, <group_cipher>,<bgn>,<wps>'

• <ecn>: encryption method
  • 0: OPEN
  • 1: WEP
  • 2: WPA_PSK
  • 3: WPA2_PSK
  • 4: WPA_WPA2_PSK
  • 5: WPA2_Enterprise (current AT does not support connection to this encrypted AP)
• <ssid>: string parameter, SSID of AP
• <rssi>: signal strength
• <mac>: string parameter, AP's MAC address
• <channel>: channel number
• <freq offset>: AP frequency offset, unit: kHz. This value is divided by 2.4 to get the ppm value.
• <freq cali>: frequency offset calibration value
• <pairwise_cipher>:
  • 0: CIPHER_NONE
  • 1: CIPHER_WEP40
  • 2: CIPHER_WEP104
  • 3: CIPHER_TKIP
  • 4: CIPHER_CCMP
  • 5: CIPHER_TKIP_CCMP
  • 6: CIPHER_UNKNOWN
• <group_cipher>: definition is the same as <pairwise_cipher>
• <bgn>: bit0 stands for b mode; bit1 stands for g mode; bit2 stands for n mode

      If the corresponding bit is 1, it indicates that the mode is enabled; if the corresponding bit is 0, the mode is not enabled.
  

• <wps>:0, WPS is not enabled; 1, WPS is enabled

example:

info_strs = ['4,"ChinaNet-lot0",-79,"c8:50:e9:e8:21:3e",1,-42,0,4,3,7,1', '4,"TOPSTEP2G4",-7
0,"f8:e7:1e:0d:0d:f8",1,-57,0,4,4,7,0']

This may seem strange, because each AP's information is a string of characters, there are integers and strings in the message, the string is enclosed in double quotes, so you need to deal with it again after getting this string, for example:

def wifi_deal_ap_info(info):
    res = []
    for ap_str in info:
        ap_str = ap_str.split(",")
        info_one = []
        for node in ap_str:
            if node.startswith('"'):
                info_one.append(node[1:-1])
            else:
                info_one.append(int(node))
        res.append(info_one)
    return res

info_strs = ['4,"ChinaNet-lot0",-79,"c8:50:e9:e8:21:3e",1,-42,0,4,3,7,1', '4,"TOPSTEP2G4",-70,"f8:e7:1e:0d:0d:f8",1,-57,0,4,4,7,0']

info = wifi_deal_ap_info(info_strs)
print(info)

The output is:

[[4, 'ChinaNet-lot0', -79, 'c8:50:e9:e8:21:3e', 1, -42, 0, 4, 3, 7, 1], [4, 'TOPSTEP2G4', -70, 'f8:e7:1e:0d:0d:f8', 1, -57, 0, 4, 4, 7, 0]]

Then for example to get every AP SSID:

for ap_info in info:
    print(ap_info[1])

2.6. enable_ap(ssid, key, chl=5, ecn=3)

Connect to the specified WiFi hotspot.

Parameters

• ssid: SSID
• key: password
• chl: channel number of the WiFi signal
• ecn: encryption method, there are OPEN``WPA2_PSK, etc., refer to the constant part of this page ESP8285, the default value is 3, which is ESP8285.WPA2_PSK, for example

  Nic = network.ESP8285(uart)
  Nic.enable_ap("maixpy", "12345678", 5, nic.OPEN)
  

  or

  Nic.enable_ap("maixpy", "12345678", 5, network.ESP8285.OPEN)
  

2.7. disable_ap()

Disconnect from the currently connected WiFi hotspot.

2.8. Constants

OPEN

No encryption and no password required.

WPA_PSK

WPA_PSK encryption

WPA2_PSK

WPA2_PSK encryption

WPA_WPA2_PSK

WPA_WPA2_PSK encryption

3. Code

Refer to [code in the network directory] (https://github.com/sipeed/MaixPy_scripts/tree/master/network)

ESP32_Module

1. network.ESP32_SPI(cs,rst,rdy,mosi,miso,sclk)

To instantiate an ESP32_SPI NIC object, you need to pass in the corresponding GPIOHS FUNC.

If the number of parameters passed in is incorrect, an error will be returned.

1.1. Parameters

• fpioa_func for pin function

1.2. Return Value

• ESP32_SPI NIC object

2. ESP32_SPI

2.1. adc

Read the adc value of the esp32 module

Parameters

None

Return Value

tuple, the adc value of 5 channels is "PIN36", "PIN39", "PIN34", "PIN35", "PIN32"

Code

demo_esp32_read_adc.py