Hello. I am involved on a voip project that aims to deliver a complete voip solution using Asterisk software. We will develop the IP phones, ATAs, and a GUI for the users configure Asterisk. My tasks relate to the design and construction of the Ip phones and ATAs.
Our aim is to develop cheap terminals, so they can get popular. For that, we plain to implement just the godec G.711 (PCM), as it require less computational processing, and so a more cheap BOM hardware.
My problem is that honestly, I don't have much experience on designing embedded systems, and I believe this kind of project is not very simple. I am looking for some guidelines on how to obtain the hardware requirements on building this system. That`s why I am posting here.
My assumptions right now is that I will not need a DSP chip, a normal microcontroller will be fine becouse the codec implementation cam be build on a separated chip, like texas instrument PCM codec chip TLV320AIC22C. So I believe all I need is a microcontroller with an ethernet interface for the network, and I2C and serial interface for the codec, and a RTOS for SIP and RTP implementation. Remember that we aim to buld the most cheap IP phone and ATA possible. Those are all assumptions for now.
So, I would like to hear from you any coments, or any help you can provide to help me complete my task, like how to choose the cheapest microcontroller and perifericals that suits this task. Thank you.
Uderman