Add RP2 PIO background read #9659
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| static void fill_buf_info_read(sm_buf_info *info, mp_obj_t obj, size_t *stride_in_bytes) { | ||
| if (obj != mp_const_none) { | ||
| info->obj = obj; | ||
| mp_get_buffer_raise(obj, &info->info, MP_BUFFER_WRITE); | ||
| size_t stride = mp_binary_get_size('@', info->info.typecode, NULL); | ||
| if (stride > 4) { | ||
| mp_raise_ValueError(MP_ERROR_TEXT("Buffer elements must be 4 bytes long or less")); | ||
| } | ||
| if (*stride_in_bytes && stride != *stride_in_bytes) { | ||
| mp_raise_ValueError(MP_ERROR_TEXT("Mismatched data size")); | ||
| } | ||
| *stride_in_bytes = stride; | ||
| } else { | ||
| memset(info, 0, sizeof(*info)); | ||
| } | ||
| } |
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Can you please combine the fill_buf_info_{read,write} routines? I notice you've added detection of mismatched stride between the "once" and "loop" variants, which should probably apply to write as well. I think you'd just have to add the access type parameter and pass MP_BUFFER_{READ,WRITE} in.
Or is there a reason the new checking you added should not also have been done for the background write case?
| //| pending: int | ||
| //| pending_write: int |
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Please document that the pending property is a deprecated alias for pending_write and will be removed in a future version of CircuitPython.
| } | ||
| MP_DEFINE_CONST_FUN_OBJ_1(rp2pio_statemachine_get_pending_write_obj, rp2pio_statemachine_obj_get_pending_write); | ||
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| const mp_obj_property_t rp2pio_statemachine_pending_write_obj = { |
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Please use the MP_PROPERTY_GETTER macro here, even though it wasn't used in the code whose style you were emultaing elsewhere in this file. We should tidy away the direct uses of const mp_obj_property_t that have not previously been done, like the other ones in this file.
| @@ -1023,121 +1047,241 @@ uint8_t rp2pio_statemachine_program_offset(rp2pio_statemachine_obj_t *self) { | |||
| return _current_program_offset[pio_index][sm]; | |||
| } | |||
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| bool common_hal_rp2pio_statemachine_background_write(rp2pio_statemachine_obj_t *self, const sm_buf_info *once, const sm_buf_info *loop, uint8_t stride_in_bytes, bool swap) { | |||
| bool common_hal_rp2pio_statemachine_background_write(rp2pio_statemachine_obj_t *self, const sm_buf_info *once_write, const sm_buf_info *loop_write, uint8_t stride_in_bytes, bool swap) { | |||
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I wouldn't personally have changed the parameter and local variables names but this is OK.
| int background_stride_in_bytes; | ||
| bool dma_completed, byteswap; | ||
| bool dma_completed_write, byteswap; |
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hmm are two byteswap values (one for read, one for write) needed?
For testing with no codec, I'm getting together a loopback example similar to https://github.com/adafruit/Adafruit_CircuitPython_PIOASM/blob/main/examples/pioasm_i2s_codec.py that will send a |
I've added a loopback example at https://github.com/timchinowsky/tac5 which you should be able to run as is on a Feather RP2040 if you connect DOUT (D9) to DIN (D10). |
This PR adds a
background_readmethod torp2pio.StateMachineto complement the existingbackground_write.