# Test machine.I2S data transfer rate, for both TX and RX. try: from machine import Pin, I2S except ImportError: print("SKIP") raise SystemExit import time, sys # Configure pins based on the board. if "pyboard" in sys.platform: i2s_id = 2 sck_pin = Pin("Y6") ws_pin = Pin("Y5") sd_tx_pin = sd_rx_pin = Pin("Y8") elif "rp2" in sys.platform: i2s_id = 1 sck_pin = Pin(0) ws_pin = Pin(1) sd_tx_pin = sd_rx_pin = Pin(2) elif "mimxrt" in sys.platform: i2s_id = 1 sck_pin = Pin(26) ws_pin = Pin(27) sd_tx_pin = Pin(7) sd_rx_pin = Pin(8) TEST_BYTES = b"01234567" RATE = 11025 # frames/sec def test(mode, sd_pin, bits_per_sample, frame_format): i2s = I2S( i2s_id, sck=sck_pin, ws=ws_pin, sd=sd_pin, mode=mode, bits=bits_per_sample, format=frame_format, rate=RATE, ibuf=200, ) if frame_format == I2S.MONO: channels = 1 else: channels = 2 bits_per_frame = bits_per_sample * channels buf_len_250ms = bits_per_frame // 8 * RATE // 4 # Create test data and preload I2S buffers. if mode == I2S.TX: mode_str = "TX" data = TEST_BYTES * (buf_len_250ms // len(TEST_BYTES)) i2s.write(data) else: mode_str = "RX" data = bytearray(len(TEST_BYTES) * (buf_len_250ms // len(TEST_BYTES))) i2s.readinto(data) # Time how long it takes to read/write 2 lots of data. t0 = time.ticks_ms() for i in range(2): if mode == I2S.TX: i2s.write(data) else: i2s.readinto(data) t1 = time.ticks_ms() dt = time.ticks_diff(t1, t0) i2s.deinit() # Print out test result, time should be in range of 500ms. print(mode_str, bits_per_sample, channels, abs(dt - 500) <= 4) test(I2S.TX, sd_tx_pin, 16, I2S.MONO) test(I2S.TX, sd_tx_pin, 16, I2S.STEREO) test(I2S.TX, sd_tx_pin, 32, I2S.MONO) test(I2S.TX, sd_tx_pin, 32, I2S.STEREO) test(I2S.RX, sd_rx_pin, 16, I2S.MONO) test(I2S.RX, sd_rx_pin, 16, I2S.STEREO) test(I2S.RX, sd_rx_pin, 32, I2S.MONO) test(I2S.RX, sd_rx_pin, 32, I2S.STEREO)