Wireless Audio - PCB & SOFTWARE
Both the transmitter module and the receiver module have been routed for a dual
layer PCB using Eagle. To keep costs low, components shall be placed on a single
side. Single sided component placement requires only one solder paste mask.
Below is the layout for the receiver module.
Prototype boards were produced by Olimex. Whilst the boards were being built, I
began looking at the software for programming of the serial EEPROM's. The
NRF24Z1 has a number of registers that need configuring at power up. This
configuration can be done in two ways.
- NRF24Z1 reads an external EEPROM via SPI or I2C.
- A microntroller programs the NRF24Z1 via I2C.
I chose option 1 as it keeps the cost down of the final board, however, the the
I2C lines that are used to provide the interface from the micro to the NRF24Z1
have been taken to the main connector so I can experiment with a micro if needs
be.
I decided to write a small VB application that reads an XML file defining all
the registers within for NRF24Z1 (I'll make it downloadable early '08). It then
generates a simple GUI that allows the user to easily configure the registers
without the need to keep refering to the datasheet (well that's the plan). The
program generates a file that can be used to program the EEPROM. Unfortunately I
dont have a EEPROM progammer, but I do have an LPC2106 eval board. I have
written a small program on the LPC2106 to receive an intel Hex file over the
serial port and use the data to program a serial EEPROM.
The boards are in! They look good.
[04/12/2007 Great the boards are in, unfortunately, I have to go to London with
work so I cant start assembling until next week :o(. I can still work on the
software so should be able to program the EEPROM shortley after the boards are
assembled. Iain ]
[22/02/08 I have to apologise for the slow progress of this project. Time is
currently not on my side :o(. I have assembled the boards, all seems ok.
However, I have not yet loaded the EEPROM's with the correct register settings.
Im hoping the current madness at work will soon stop so I can start getting home
at a reasonable time. Iain]