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nimphea_dac

Nim wrapper for libDaisy DAC (Digital to Analog Converter) peripheral.

The DAC provides analog voltage output on dedicated pins:

DAC Channel 1: PA4
DAC Channel 2: PA5

Supports both polling mode (single value writes) and DMA mode (buffered output).

Example (Polling Mode):

import nimphea/per/dac

var dac: DacHandle
var config = DacConfig(
  target_samplerate: 48000,
  chn: DAC_CHN_ONE,
  mode: DAC_MODE_POLLING,
  bitdepth: DAC_BITS_12,
  buff_state: DAC_BUFFER_ENABLED
)

if dac.init(config) == DAC_OK:
  dac.writeValue(DAC_CHN_ONE, 2048)  # Mid-range voltage

Types

DacBitDepth {.importcpp: "daisy::DacHandle::BitDepth", size: 4.} = enum DAC_BITS_8 = 0, ## 8-bit resolution DAC_BITS_12 = 1 ## 12-bit resolution: DAC resolution Source Edit
DacBufferState {.importcpp: "daisy::DacHandle::BufferState", size: 4.} = enum DAC_BUFFER_ENABLED = 0, ## Output buffer enabled for higher drive DAC_BUFFER_DISABLED = 1 ## Output buffer disabled: DAC output buffer state Source Edit
DacCallback = proc (output: ptr ptr uint16; size: csize_t) {.cdecl.}: Callback for DMA mode Called when buffer needs to be filled For dual channel: output0 = channel 1, output1 = channel 2 Source Edit
DacChannel {.importcpp: "daisy::DacHandle::Channel", size: 4.} = enum DAC_CHN_ONE = 0, ## Channel 1 (PA4) DAC_CHN_TWO = 1, ## Channel 2 (PA5) DAC_CHN_BOTH = 2 ## Both channels: DAC channel selection Source Edit
DacConfig {.importcpp: "daisy::DacHandle::Config".} = object target_samplerate*: uint32 ## Target sample rate in Hz (DMA mode only, default 48000) chn*: DacChannel ## Channel selection mode*: DacMode ## Operation mode bitdepth*: DacBitDepth ## Bit depth buff_state*: DacBufferState ## Buffer state: DAC configuration structure Source Edit
DacHandle {.importcpp: "daisy::DacHandle", header: "per/dac.h".} = object: DAC peripheral handle Source Edit
DacMode {.importcpp: "daisy::DacHandle::Mode", size: 4.} = enum DAC_MODE_POLLING = 0, ## Blocking single-value writes DAC_MODE_DMA = 1 ## DMA-driven buffered output: DAC operation mode Source Edit
DacResult {.importcpp: "daisy::DacHandle::Result", size: 4.} = enum DAC_OK = 0, DAC_ERR = 1: Return values for DAC operations Source Edit

Procs

proc getConfig(this: DacHandle): DacConfig {.importcpp: "#.GetConfig()", ...raises: [], tags: [], forbids: [].}: Get current DAC configuration

Returns: Current configuration
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proc init(this: var DacHandle; config: DacConfig): DacResult {. importcpp: "#.Init(#)", ...raises: [], tags: [], forbids: [].}: Initialize the DAC peripheral

Parameters:

config - DAC configuration

Returns: DAC_OK on success, DAC_ERR on failure
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proc start(this: var DacHandle; buffer1: ptr uint16; buffer2: ptr uint16; size: csize_t; cb: DacCallback): DacResult {. importcpp: "#.Start(#, #, #, #)", ...raises: [], tags: [], forbids: [].}: Start DAC in DMA mode (dual channel)

Parameters:

buffer1 - Output buffer for channel 1

buffer2 - Output buffer for channel 2

size - Buffer size in samples

cb - Callback function

Returns: DAC_OK on success
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proc start(this: var DacHandle; buffer: ptr uint16; size: csize_t; cb: DacCallback): DacResult {.importcpp: "#.Start(#, #, #)", ...raises: [], tags: [], forbids: [].}: Start DAC in DMA mode (single channel)

Parameters:

buffer - Output buffer

size - Buffer size in samples

cb - Callback function

Returns: DAC_OK on success, DAC_ERR if using both channels
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proc stop(this: var DacHandle): DacResult {.importcpp: "#.Stop()", ...raises: [], tags: [], forbids: [].}: Stop DAC conversion

Returns: DAC_OK on success
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proc writeValue(this: var DacHandle; chn: DacChannel; val: uint16): DacResult {. importcpp: "#.WriteValue(#, #)", ...raises: [], tags: [], forbids: [].}: Write value in polling mode

Has no effect in DMA mode.

Parameters:

chn - Channel to write to

val - Value to write (0-255 for 8-bit, 0-4095 for 12-bit)

Returns: DAC_OK on success
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