AnsweredAssumed Answered

FSMC - Disable "burst" writes

Question asked by ryan on Feb 26, 2016
Latest reply on Mar 1, 2016 by waclawek.jan
I'm using the FSMC in the STM32L4, but can't figure out how to disable "burst" writes.
By this, I mean that multiple writes happen within a single CS.
When I do multiple writes in a row to external memory, sometimes these writes get "grouped" into a single chip select. If I add some __NOP()'s or enough instructions between, the writes occur correctly.

Here's my configuration, which is basically taken straight from the CUBE example code:
hsram.Instance  = FMC_NORSRAM_DEVICE;
/* SRAM device configuration */ 
SRAM_Timing.AddressSetupTime       = 1;
SRAM_Timing.AddressHoldTime        = 1;
SRAM_Timing.DataSetupTime          = 1;
SRAM_Timing.BusTurnAroundDuration  = 0;
SRAM_Timing.CLKDivision            = 2;
SRAM_Timing.DataLatency            = 0;
SRAM_Timing.AccessMode             = FMC_ACCESS_MODE_A;
hsram.Init.NSBank             = FMC_NORSRAM_BANK1;
hsram.Init.DataAddressMux     = FMC_DATA_ADDRESS_MUX_DISABLE;
hsram.Init.MemoryType         = FMC_MEMORY_TYPE_SRAM;
hsram.Init.MemoryDataWidth    = FMC_NORSRAM_MEM_BUS_WIDTH_8;
hsram.Init.BurstAccessMode    = FMC_BURST_ACCESS_MODE_DISABLE;
hsram.Init.WaitSignalPolarity = FMC_WAIT_SIGNAL_POLARITY_LOW;
hsram.Init.WaitSignalActive   = FMC_WAIT_TIMING_BEFORE_WS;
hsram.Init.WriteOperation     = FMC_WRITE_OPERATION_ENABLE;
hsram.Init.WaitSignal         = FMC_WAIT_SIGNAL_DISABLE;
hsram.Init.ExtendedMode       = FMC_EXTENDED_MODE_DISABLE;
hsram.Init.AsynchronousWait   = FMC_ASYNCHRONOUS_WAIT_DISABLE;
hsram.Init.WriteBurst         = FMC_WRITE_BURST_DISABLE;
hsram.Init.ContinuousClock    = FMC_CONTINUOUS_CLOCK_SYNC_ASYNC;
hsram.Init.WriteFifo          = FMC_WRITE_FIFO_DISABLE;
hsram.Init.PageSize           = FMC_PAGE_SIZE_NONE;

When I do a bunch of writes in a row, here's what I get. (I've inserted some __NOP()'s toward the beginning to show you what it should look like.)


In case it isn't clear, I'm using the FSMC asynchronously, so I thought this sort of bursting would be disabled. And furthermore, I have this: FMC_WRITE_BURST_DISABLE.