Dogbone06
Well-known member
I've found some info on how to change the i2s pins for Teensy 3, but no real forward way for Teensy 4.
I think I know the place where it needs to be done, but there's probably more to it.
In file libraries\Audio\output_i2s.cpp
I am using these pins:
Is there a proper way to set alternate i2s?
I think I know the place where it needs to be done, but there's probably more to it.
In file libraries\Audio\output_i2s.cpp
Code:
CCM_CCGR5 |= CCM_CCGR5_SAI1(CCM_CCGR_ON);
// if either transmitter or receiver is enabled, do nothing
if (I2S1_TCSR & I2S_TCSR_TE) return;
if (I2S1_RCSR & I2S_RCSR_RE) return;
// not using MCLK in slave mode - hope that's ok?
//CORE_PIN23_CONFIG = 3; // AD_B1_09 ALT3=SAI1_MCLK
CORE_PIN21_CONFIG = 3; // AD_B1_11 ALT3=SAI1_RX_BCLK
CORE_PIN20_CONFIG = 3; // AD_B1_10 ALT3=SAI1_RX_SYNC
IOMUXC_SAI1_RX_BCLK_SELECT_INPUT = 1; // 1=GPIO_AD_B1_11_ALT3, page 868
IOMUXC_SAI1_RX_SYNC_SELECT_INPUT = 1; // 1=GPIO_AD_B1_10_ALT3, page 872
// configure transmitter
I2S1_TMR = 0;
I2S1_TCR1 = I2S_TCR1_RFW(1); // watermark at half fifo size
I2S1_TCR2 = I2S_TCR2_SYNC(1) | I2S_TCR2_BCP;
I2S1_TCR3 = I2S_TCR3_TCE;
I2S1_TCR4 = I2S_TCR4_FRSZ(1) | I2S_TCR4_SYWD(31) | I2S_TCR4_MF
| I2S_TCR4_FSE | I2S_TCR4_FSP | I2S_RCR4_FSD;
I2S1_TCR5 = I2S_TCR5_WNW(31) | I2S_TCR5_W0W(31) | I2S_TCR5_FBT(31);
// configure receiver
I2S1_RMR = 0;
I2S1_RCR1 = I2S_RCR1_RFW(1);
I2S1_RCR2 = I2S_RCR2_SYNC(0) | I2S_TCR2_BCP;
I2S1_RCR3 = I2S_RCR3_RCE;
I2S1_RCR4 = I2S_RCR4_FRSZ(1) | I2S_RCR4_SYWD(31) | I2S_RCR4_MF
| I2S_RCR4_FSE | I2S_RCR4_FSP;
I2S1_RCR5 = I2S_RCR5_WNW(31) | I2S_RCR5_W0W(31) | I2S_RCR5_FBT(31);
I am using these pins:
Is there a proper way to set alternate i2s?