Goal: To build a very small device to playback pre-recorded audio and send a 3 volt supply multiple times for different lengths of time during that playback.
Details: The device will perform multiple functions.
1) It will allow for recording of a person’s voice using a bitrate level of around 16 kb/s
a. The length of the recording can be upwards of 10 minutes
b. The quality of voice should balance with the ability to record up to 10 minutes and the cost per chip that is chosen. The order of importance is: time, voice quality, cost
c. Can erase and re-record
2) Even though the recording will actually be one continuous sound file, as far as the device is concerned, it needs the ability to logically be broken into “sections” so that only certain parts, or sections of the recording are activated with a physical switch/connection
a. The amount of physical switch/connections can vary from 1 – 30 (Yes this means there will be up to 30 connection/wires hanging off the device.)
3) During playback, a 3 volt signal will be set to high/on for any duration of choice any amount of times per logical section.
i. Example, The person in the recording says, “Thank you for calling ABC incorporated, please hold” Through code that can be modified for duration of each word, the voltage will only go high/on for each word and low/off for the silent short gaps of empty space between the words. Using the previous sentence as an example, “thank” might go high for 100 milliseconds, where the word “incorporated” might go high for 300 milliseconds with brief power outages for the dead space in the speech.
4) The device will run battery powered, as such – it should be designed with power conservation kept in mind at all times
5) The speaker chosen should be as cheap as possible, yet be balanced with the ability to reproduce the same recorded bitrate to the human ear
6) As for the actual recording of the sound file and getting it on the device, it is preferred that the file be recorded digitally else ware, and then transferred onto the chip, via, say usb or direct memory access in some fashion. There should not be a microphone on the unit.
7) PIC should be programmed in assembly, if the developer fells C is necessary – please present a valid reason of the pros and cons.
8) A full PCB layout diagram detailing the board layout and part numbers should be included
9) Try to use parts that will have a long availability of shelf life purchasing
This will be a kind of “prototype” and if the proof of concept works well, future work on this project will be heavy.
9 freelancers are bidding on average $674 for this job
Hi i have a good experience in PIC microcontrollers and have PICKIT2 programmer with PIC16F, PIC18F, DSPIC30F hardware . With my 9 years of experience in PIC microcontrollers, i can serve you better.