Works with I2S compat mode with BCLK mode set to 0 on AK4619.

Author: efairbanks

libraries/I2S/src/pio_i2s.pio

@@ -110,15 +110,15 @@ lastbit:
 ; to be 32 (as per the TDM specs)
 ;                           +----- WCLK
 ;                           |+---- BCLK
-    mov x, y         side 0b00 [1]
+    mov x, y         side 0b01 [1]
 bitloop:
-    out pins, 1      side 0b01    ; Output changes on rising edge
-    in pins, 1       side 0b01    ; Sample input on rising edge
-    jmp x-- bitloop  side 0b00 [1]
+    out pins, 1      side 0b00      ; Output changes on falling edge
+    in pins, 1       side 0b00      ; Sample input on falling edge
+    jmp x-- bitloop  side 0b11 [1]  ; Last bit toggles WCLK to mark frame boundary
 
-lastbit:             ; Last bit toggles WCLK to mark frame boundary
-    in pins, 1       side 0b11
-    out pins, 1      side 0b11
+lastbit:
+    in pins, 1       side 0b10
+    out pins, 1      side 0b10
     ; Loop back to the beginning
 
 
@@ -128,15 +128,15 @@ lastbit:             ; Last bit toggles WCLK to mark frame boundary
 ; to be 32 (as per the TDM specs)
 ;                           +----- WCLK
 ;                           |+---- BCLK
-    mov x, y         side 0b00 [1]
+    mov x, y         side 0b10 [1]
 bitloop:
-    out pins, 1      side 0b10    ; Output changes on rising edge
-    in pins, 1       side 0b10    ; Sample input on rising edge
-    jmp x-- bitloop  side 0b00 [1]
+    out pins, 1      side 0b00      ; Output changes on falling edge
+    in pins, 1       side 0b00      ; Sample input on falling edge
+    jmp x-- bitloop  side 0b11 [1]  ; Last bit toggles WCLK to mark frame boundary
 
-lastbit:             ; Last bit toggles WCLK to mark frame boundary
-    in pins, 1       side 0b11
-    out pins, 1      side 0b11
+lastbit:
+    in pins, 1       side 0b01
+    out pins, 1      side 0b01
     ; Loop back to the beginning
 
 

libraries/I2S/src/pio_i2s.pio.h

@@ -202,12 +202,12 @@ static inline pio_sm_config pio_tdm_out_swap_program_get_default_config(uint off
 
 static const uint16_t pio_tdm_inout_program_instructions[] = {
             //     .wrap_target
-    0xa122, //  0: mov    x, y            side 0 [1] 
-    0x6801, //  1: out    pins, 1         side 1     
-    0x4801, //  2: in     pins, 1         side 1     
-    0x0141, //  3: jmp    x--, 1          side 0 [1] 
-    0x5801, //  4: in     pins, 1         side 3     
-    0x7801, //  5: out    pins, 1         side 3     
+    0xa922, //  0: mov    x, y            side 1 [1] 
+    0x6001, //  1: out    pins, 1         side 0     
+    0x4001, //  2: in     pins, 1         side 0     
+    0x1941, //  3: jmp    x--, 1          side 3 [1] 
+    0x5001, //  4: in     pins, 1         side 2     
+    0x7001, //  5: out    pins, 1         side 2     
             //     .wrap
 };
 
@@ -239,12 +239,12 @@ static inline pio_sm_config pio_tdm_inout_program_get_default_config(uint offset
 
 static const uint16_t pio_tdm_inout_swap_program_instructions[] = {
             //     .wrap_target
-    0xa122, //  0: mov    x, y            side 0 [1] 
-    0x7001, //  1: out    pins, 1         side 2     
-    0x5001, //  2: in     pins, 1         side 2     
-    0x0141, //  3: jmp    x--, 1          side 0 [1] 
-    0x5801, //  4: in     pins, 1         side 3     
-    0x7801, //  5: out    pins, 1         side 3     
+    0xb122, //  0: mov    x, y            side 2 [1] 
+    0x6001, //  1: out    pins, 1         side 0     
+    0x4001, //  2: in     pins, 1         side 0     
+    0x1941, //  3: jmp    x--, 1          side 3 [1] 
+    0x4801, //  4: in     pins, 1         side 1     
+    0x6801, //  5: out    pins, 1         side 1     
             //     .wrap
 };