Posted on May 17, 2011 at 13:14 When I write a data (16bit) to the GRAM of a TFT LCD through the FSMC like this:
*(u16 *)(Bank1_SRAM4_ADDR ) = Para;
I found that the ''WR'' pin generated two negative pulse,but not one pulse, RS pin(A0) was low when the first ''WR'' pulse issued while high when the second ''WR'' pulse issued, so it wrote the wrong data to the GRAM. what caused this?
anyone can help me? some codes listed below:
#define Bank1_SRAM4_ADDR ((u32)0x6C000001)// for LCD control reg
#define Bank1_SRAM4_ADDR_RS ((u32)0x6C000000)// for LCD status reg
p.FSMC_AddressSetupTime = 1;
p.FSMC_AddressHoldTime = 0;
p.FSMC_DataSetupTime = 5;
p.FSMC_BusTurnAroundDuration = 5;
p.FSMC_CLKDivision = 0;
p.FSMC_DataLatency = 0;
p.FSMC_AccessMode = FSMC_AccessMode_B;
FSMC_NORSRAMInitStructure.FSMC_Bank = FSMC_Bank1_NORSRAM4;
FSMC_NORSRAMInitStructure.FSMC_DataAddressMux = FSMC_DataAddressMux_Disable;
FSMC_NORSRAMInitStructure.FSMC_MemoryType = FSMC_MemoryType_SRAM;
FSMC_NORSRAMInitStructure.FSMC_MemoryDataWidth = FSMC_MemoryDataWidth_16b;
FSMC_NORSRAMInitStructure.FSMC_BurstAccessMode = FSMC_BurstAccessMode_Disable;
FSMC_NORSRAMInitStructure.FSMC_WaitSignalPolarity = FSMC_WaitSignalPolarity_Low; //Low
FSMC_NORSRAMInitStructure.FSMC_WrapMode = FSMC_WrapMode_Disable;
FSMC_NORSRAMInitStructure.FSMC_WaitSignalActive = FSMC_WaitSignalActive_BeforeWaitState;
FSMC_NORSRAMInitStructure.FSMC_WriteOperation = FSMC_WriteOperation_Enable;
FSMC_NORSRAMInitStructure.FSMC_WaitSignal = FSMC_WaitSignal_Disable;
FSMC_NORSRAMInitStructure.FSMC_ExtendedMode = FSMC_ExtendedMode_Disable;
FSMC_NORSRAMInitStructure.FSMC_AsyncWait = FSMC_AsyncWait_Disable;
FSMC_NORSRAMInitStructure.FSMC_WriteBurst = FSMC_WriteBurst_Disable;
FSMC_NORSRAMInitStructure.FSMC_ReadWriteTimingStruct = &p;
FSMC_NORSRAMInitStructure.FSMC_WriteTimingStruct = &p;
FSMC_NORSRAMInit(&FSMC_NORSRAMInitStructure);
FSMC_NORSRAMCmd(FSMC_Bank1_NORSRAM4, ENABLE); /*Enable FSMC Bank1_SRAM4 Bank */
*(u16 *)(Bank1_SRAM4_ADDR ) = Para;
