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1Assemble board.
The RN4677 should be installed first. The package I used for it contains enough exposed pad area so it can be hand soldered with a 1/16" chisel tip.
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2Assemble plug.
The USB A/B connector consists of the plug and top & bottom shell halves. You'll need a length of 4 or 5 conductor signal wire, no larger than 28AWG.
The Eagle schematic contains the pin assignment.
Don't connect the cable to the board yet unless you don't want to customize the RN4677 settings in the next step.
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3Customize RN4677 settings.
You should have the Microchip RN4677 Bluetooth® 4.0 Dual Mode Module User’s Guide handy for this step. Familiarize yourself with the command syntax and how to enter/exit command mode.
First connect the Rx & Tx lines to an RS232 port on a computer. IMPORTANT: make sure the signal levels from the computer are compatible with 5V TTL. Standard RS232 from a DB9/25 on a PC are much higher and will destroy the unit.
Load a terminal emulator, connect to the RS232 port and make sure flow control is disabled. Set the baud rate to 115.2Kbps, 8 data bits, 1 stop, no parity.
Decide on a name for your dongle like "BTCON". You'll use it in the following commands (reference guide for exact syntax):
- Device name - SN,
- Service name - SS,
- Serialized friendly name - S-,
It's also a good idea to clear the extended status string. This is a string sent to the MCU when a Bluetooth connection is established. This ensures it doesn't get interpreted as a command: SO, . Note that there's a space after the comma. The space is what clears the default string.
These settings are stored in NVM but won't display until the unit is rebooted or power cycled.
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4Connect cable to board.
Make sure you've routed the cable thru the enclosure if using one.
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5Test & enjoy.
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