I've been doing this for a very long time ago for PSoC Creator 2.1
This project consists of:
1. The test signal generator, which has 2 modes
a. the default signal is sine
b. the signal downloaded from the file on the SD card.
2. An ADC (12 bits) whose signal is written in real time to a file on the SD card with a speed of up to 25,000 samples per second using DMA.
Each next entry is made into a new file.
Unfortunately SD card value - no more than 2 (4?) GB
I can not answer you - I left to travel.