MapMem to read SPI0 registers on VF61

Technical Support
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1

In the past I used MapMem library to read USB registers on VF61 running Win CE 6.
Now I’m trying to follow the same approach to read the registers related to SPI0 (SPI0_MCR, SPI0_TCR, SPI0_CTAR0, …). I wrote this code

void Read_Spi_Registers(void)
{
	HANDLE hMapMem = NULL;            ///< handle to the MapMem library
	BOOL success;
	DWORD	SPI0_MCR;
	DWORD *reg;

	// === Initialize MapMem library. ===
	hMapMem = Map_Init();   
	ASSERT(hMapMem != 0);

	reg = (DWORD *)Map_MapMemory((DWORD)0x4002C000, 4);
	SPI0_MCR = *reg;
	Map_UnMapMemory(reg);
	wprintf(L"SPI0_MCR =\r\n\t0x%08X\r\n", SPI0_MCR);

	// === De-Initialize MapMem library ===
	success = Map_Deinit(hMapMem);
	ASSERT(success);

	return;
}

but I get an exception.
I suspect this is related to the clock of the peripheral not enabled (the same issue described here), but I don’t find any way to get it working.
Looking at VybClk_EnableClock(), I don’t see any tVybClkId for SPI0.

2

After a deeper investigation, I’m not so sure the problem is in the clock, since SPI0 peripheral works as expected (I checked with an oscilloscope).

3

you can find the spi clock id in clk_vyb.h with the following name

clkSpi0 = 12,
clkSpi1 = 13

I made some changes in your code & now it is working fine.

void Read_Spi_Registers(void)
 {
     HANDLE hMapMem = NULL;            ///< handle to the MapMem library
     BOOL success;
     DWORD    SPI0_MCR;
     DWORD *reg;
     HANDLE hclk ;

    //===Initialize clock ====
	 hclk = VybClk_Init(NULL);
	 VybClk_EnableClock(hclk , 12, TRUE);
	
     // === Initialize MapMem library. ===
     hMapMem = Map_Init();   
     ASSERT(hMapMem != 0);
 
     reg = (DWORD *)Map_MapMemory((DWORD)0x4002C000, 4);
     SPI0_MCR = *reg;
     Map_UnMapMemory(reg);
     wprintf(L"SPI0_MCR =\r\n\t0x%08X\r\n", SPI0_MCR);

    // to deinit clock
	// VybClk_Deinit(hclk);
 
     // === De-Initialize MapMem library ===
     success = Map_Deinit(hMapMem);
     ASSERT(success);
 
     return;
}
4

It works. I missed the entries for clkSpi0 and clkSpi1.
Thanks