Sound
Hello Norm,
I wish to thank you for all your answers. Clear and it answers exactly my questions.
When you say: "The data has already been processed from the original wave file by the PC program."
-> you mean by your program that dumps the sound file to the memory chip or by the program that recorded/converted the sound? In other words, would the sound file (wave, 44KHz, 16 bits) I found in a game sound directory be ready to be stored in the memory chip? Can I transfer the wave file 'bit per bit' into a memory chip or does the file need to be modified to be used by the dac? I guess there is a header, a trailer, a checksum and stuff like this I should get rid of first. I will read the wave file specs...
"16 bits (0-65535) increases the number of steps of volume available per sample compared to 8 bits (0-255),"
-> Right, aft(er posting the questions I googled to find the answer. I undesrtand now. Thanks.
"The largest eeprom in the PIC18 series is only 1024 bytes.
Even if loaded to ram the PIC18F4620 can hold only 15 128 element word arrays or only 1.92k of word samples.
Audio memory requires massive capacity and high speed."
-> Yes, I understand. Maybe I could try an external EEPROM (I already use one for my project), I have to check if it has a SPI interface and if it can be accessed at a frequency compatible with the sound frequency.
I found the microchip 25AA1024 1Mbits SPI bus serial EEPROM. It has 246 bytes page size, and a 20MHz clock speed.
It could store my 44K words of my 1s sound at 16bits 44KHz.
I guess it could replace the M25P32 memory chip...
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