Changes

2,335 bytes added , 03:25, 21 March 2010

New page: Sample (pseudo) sourcecode to talk with the CODEC SPI interface. Used for example to interface with the touchscreen. <source lang=cpp> static u32 cdcCurrentPage = 99; u32 TouchReadBuf...

Sample (pseudo) sourcecode to talk with the CODEC SPI interface.

Used for example to interface with the touchscreen.

<source lang=cpp>

static u32 cdcCurrentPage = 99;

u32 TouchReadBuffer(...)
{
// Check if panel is touched (one of these 2):
// val = CDC_ReadRegisterEx(3, 9)
// val = CDC_ReadRegisterEx(3, 14)

// if touched, read touch data into buf (2 bytes per touch position)
// CDC_ReadRegistersEx(252, 1, buf, 20)
}

void CDC_ChangePage(u32 page)
{
if (cdcCurrentPage == page)
return;

if (cdcCurrentPage == 0xFF)
CDC_WriteRegister(0x7F, page);
else
CDC_WriteRegister(0, page);

cdcCurrentPage = page;
}

void CDC_WriteRegister(u32 reg, u32 val)
{
while(REG_SPICNT & 0x80);

REG_SPICNT = 0x8A00;
REG_SPIDATA = (reg<<1) & 0xFF;

while(REG_SPICNT & 0x80);

REG_SPICNT = 0x8200;
REG_SPIDATA = val & 0xFF;
}

void CDC_WriteRegisterEx(u32 page, u32 reg, u32 val)
{
CDC_ChangePage(page);
CDC_WriteRegister(reg, val);
}

void CDC_WriteRegisters(u32 reg, u8* buf, u32 size)
{
if (size == 0)
return;

while(REG_SPICNT & 0x80);

REG_SPICNT = 0x8A00;
REG_SPIDATA = (reg<<1) & 0xFF;

while(REG_SPICNT & 0x80);

while(size-- > 1)
{
REG_SPIDATA = 0;

while(REG_SPICNT & 0x80);

*buf++ = REG_SPIDATA;
}

REG_SPICNT = 0x8200;
REG_SPIDATA = 0;

while(REG_SPICNT & 0x80);

*buf++ = REG_SPIDATA;
}

void CDC_WriteRegistersEx(u32 page, u32 reg, u8* buf, u32 size)
{
CDC_ChangePage(page);
CDC_WriteRegisters(reg, buf, size);
}

u32 CDC_ReadRegister(u32 reg)
{
while(REG_SPICNT & 0x80);

REG_SPICNT = 0x8A00;
REG_SPIDATA = ((reg<<1) | 1) & 0xFF;

while(REG_SPICNT & 0x80);

REG_SPICNT = 0x8200;
REG_SPIDATA = 0;

while(REG_SPICNT & 0x80);

return REG_SPIDATA;
}

u32 CDC_ReadRegisterEx(u32 page, u32 reg)
{
CDC_ChangePage(page);
return CDC_ReadRegister(reg);
}

void CDC_ReadRegisters(u32 reg, u8* buf, u32 size)
{
if (size == 0)
return;

while(REG_SPICNT & 0x80);

REG_SPICNT = 0x8A00;
REG_SPIDATA = ((reg<<1)|1) & 0xFF;

while(REG_SPICNT & 0x80);

while(size-- > 1)
{
REG_SPIDATA = 0;

while(REG_SPICNT & 0x80);

*buf++ = REG_SPIDATA;
}

REG_SPICNT = 0x8200;
REG_SPIDATA = 0;

while(REG_SPICNT & 0x80);

*buf++ = REG_SPIDATA;
}

void CDC_ReadRegistersEx(u32 page, u32 reg, u8* buf, u32 size)
{
CDC_ChangePage(page);
CDC_ReadRegisters(reg, buf, size);
}
</source>

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Changes

Sourcecode/codec.c (view source)

Revision as of 03:25, 21 March 2010