TUSR_SRAM_SHIFT
#define TUSR_SRAM_32K (0U << TUSR_SRAM_SHIFT)
#define TUSR_SRAM_48K (1U << TUSR_SRAM_SHIFT)
#define TUSR_SRAM_16K (2U << TUSR_SRAM_SHIFT)
#define TUSR_SRAM_64K (3U << TUSR_SRAM_SHIFT)