# MI_DmaSend*

## Syntax

  `#include <nitro/mi.h>`
  `void MI_DmaSend32( u32 dmaNo,
  const void* src,
  volatile void* dest,
  u32 size );
  `
  `void MI_DmaSend32_SetUp( u32 dmaNo,
  const void* src,
  volatile void* dest,
  u32 size );
  `
  `void MI_DmaSend16( u32 dmaNo,
  const void* src,
  volatile void* dest,
  u32 size );`
  `void MI_DmaSend16_SetUp( u32 dmaNo,
  const void* src,
  volatile void* dest,
  u32 size );`
  `void MI_DmaSend32Async( u32 dmaNo,
  const void* src,
  volatile void* dest,
  u32 size,
  MIDmaCallback callback,
  void* arg );`
  `void MI_DmaSend32Async_SetUp( u32 dmaNo,
  const void* src,
  volatile void* dest,
  u32 size,
  MIDmaCallback callback,
  void* arg );`
  `void MI_DmaSend16Async( u32 dmaNo,
  const void* src,
  volatile void* dest,
  u32 size,
  MIDmaCallback callback,
  void* arg );`
  `void MI_DmaSend16Async_SetUp( u32 dmaNo,
  const void* src,
  volatile void* dest,
  u32 size,
  MIDmaCallback callback,
  void* arg );`

## Arguments

dmaNo | DMA channel used.
src | The transfer source address.
dest | The transfer destination address.
size | Transfer size.
callback | Callback when DMA ends.
arg | Callback argument when DMA ends.

## Return Values

None.

## Description

Uses DMA to send data to the same address.
The function does not change the address of the transfer destination. It increments only the transfer origin address, and repeatedly transfers contiguous region data to the same address.

The `*_SetUp` functions only configure the given settings without actually performing DMA. To actually start DMA, call the `MI_DmaRestart` function.

The `MI_DmaSend16*` functions transfer in 16-bit units. Both the transfer source address and the transfer destination address must be 2-byte aligned. The `MI_DmaSend16*` functions transfer in 32-bit units. Both the transfer source address and the transfer destination address must be 4-byte aligned.

`MI_DmaSend16()` and `MI_DmaSend32()` wait within the function until DMA completes. `MI_DmaSend16Async()` and `MI_DmaSend32Async()` call a callback function when DMA ends. The callback, `callback`, is a `MIDmaCallback` type (a `void` type function that takes one `void*` argument). `callback` is called from the system DMA interrupt handler and therefore is called while interrupts are prohibited.

It is necessary to understand how to use Async-type APIs in order to obtain maximum functionality. Refer to the `MI_DmaCopy` function for more information about this.

###
DMA Controller Bugs

See the section titled "DMA Controller Bugs" in the reference for the `MI_DmaCopy` function.

## Internal Operation

Uses the following IO registers: DMAn source register (0x40000B0 + 12n), DMAn destination register (0x40000B4 + 12n), and DMAn control register (0x40000B8 + 12n). (n is the DMA channel used.))

## See Also

`MI_DmaCopy*
MI_DmaFill*
MI_DmaClear*
MI_DmaRecv*
MI_CpuSend*
MI_DmaRestart
`

## Revision History

2009/11/20 Added a description of bugs for the DMA controller.
2007/10/31 Added `_SetUp()`.
2005/03/08 Standardized the notation used for the term "interrupt" in Japanese.
2004/12/22 Added a description of calling the callback.
2004/01/30 Initial version.

CONFIDENTIAL