Novalab NL72742 User Manual

NovaLab Merlin-2 Radio Board Interface Manual

Rev 2.0 8/3/2010

This document describes how to integrate the NovaLab Merlin-2 radio into a system.

The interface to/from the NL radio board (Merlin-2) consists of three connectors:

• Power

• Signal

• Programming/Aux

Power

The power interface is a four pin, 2mm center-to-center connector. The pinout is as
follows:

1,2 Power – Unregulated power that provides the board power through a Micrel 5233

3.3V regulator. Voltage range is 3.5-12VDC at 50mA max.
Also, provides power through a second linear regulator for the PA. Max
current draw is approximately 350mA. Max 5% duty cycle max.

3,4 GND

Signal Interface Connector J2

The signal interface connector is a ten pin, 2mm center-to-center connector. The pinout
is as follows:

1. Analog input 1, Digital I/O.

2. Analog input 0, Digital I/O.

3. SPI SSn

4. PB1 – Digital I/O.

5. SPI SCK

6. SPI MOSI

7. Attnention – HW Handshake Line (Output)

8. SPI MISO

9. Regulated 3.3V from radio digital supply

10. Radio DIG1 Output

Programming/AUX Connector J4

This is a ten pin connector with 2mm center-to-center spacing. It is arranged in a 5x2
pattern. The pinout is as follows:

1. External Watchdog Reset. Toggled every time SW goes through the main

loop for external watchdog reset. Needs to be cycled at least every ½ second.

2. NC

3. PDI Data (Processor JTAG interface)

4. Wakeup – HW Handshake Line (Output)

5. RESET/n – Processor Reset – Should be pulled high on motherboard.

6. NC

7. UART TX

8. UART RX

9. NC

10. NC