Datasheet

When the Propeller microcontroller is transmitting data, but the USB host is not processing it, the red

RX←P31 LED may remain unlit.

17) Wireless Activity Lights

These DO/DI/ASSOC Wireless Activity LEDs give a visual indicator the state of the module connected to

the wireless programming and communications socket. The blue DO LED indicates the wireless module is

outputting data, the red DI LED indicates the module is inputting data, and the blue ASSOC LED indicates

that the wireless module is associated with a network. See 11) WX Wireless Access & Communication

Header, p. 4, for more information.

18) microSD Card Socket

The socket allows applications to access files from a microSD card. Uses include:

• Accessing large lookup tables

• Playing audio files

• Data logging

This socket is hardwired to I/O pins: P22 - DO (data out); P23 - CLK (clock); P24 - DI/CD (data in and

card detect); P25 - /CS (active low chip select).

19) WX Wireless Communication Module Socket

Use the Wireless Communication Module Socket for programming and communicating, using the Parallax

WX ESP8266 WiFi Module - DIP, or for communicating only, with other wireless RF modules, such as the

XBee S1 and SB6 Wi-Fi modules.

When programmed by the Parallax WX ESP8266 WiFi Module, the Propeller Activity Board WX

automatically selects the Wireless Communication Module Socket for serial communications on Propeller

I/O pins P30 and P31. To override the selection, see 11) WX Wireless Access & Communication Header,

p. 4.

NOTE: When overriding the selection to select the USB port, the override will disable programming from

the Parallax WX ESP8266 WiFi Module. Communications will still be possible, but only by connecting to

the Wireless Access & Communication Hea d e r.

NOTE: When Rev A of the Propeller Activity Board WX is not connected to a USB host or charger, and the

Wireless Communication Socket is automatically selected, the automatic selection system may switch to

the disconnected USB input. This may prevent successful programming or interrupt communications.

When programming or communicating through the Wireless Communication Socket with Rev A of the

Propeller Activity Board WX when a USB host or charger is not present, connect the SEL socket to 3.3V, to

override the automatic selection.

If this socket is selected for Propeller chip programming and communications, serial messages from a

host computer or other device will be transmitted by the wireless module’s DO pin, and received by

Propeller I/O pin P31. Serial messages transmitted by Propeller I/O pin P30 will be routed to the wireless

module’s DI pin and then relayed to the host computer or other serial device.

NOTE: This socket does not support the older Digi XBee S6 Wi-Fi module; the S6B or later is required for

operation with a Digi Wi-Fi module.