Stm32l4R9AII6 Custom Board External Sram W/R Problem

[snnzdmr1]

Hi,

I am using 16Mbit Sram (IS61WV102416DBLL)

The Sram-MCU (STM32L4R9AII6) schematic is as follows

"Chip Select NE1" default pins are used on the MCU side

I added FMC and detailed pin Configuration as "fmc_ram.pdf"

Code :

#define SRAM_BANK_ADDR          (uint32_t)0x60000000
#define LEN		                         100
 
uint16_t tx[LEN];
uint16_t rx[LEN];
 
int main(void)
{
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  MX_FMC_Init();
  for(uint16_t i=0;i<LEN;i++){  // fill tx Buffer
	  tx[i] = i;
  }
  HAL_SRAM_Write_16b(&hsram1,(uint32_t *)SRAM_BANK_ADDR, tx, LEN);
  HAL_SRAM_Read_16b(&hsram1,(uint32_t *)SRAM_BANK_ADDR, rx, LEN);
  while (1);
}

why is it increasing by 2 steps ?