FlexSPI + QSPI NOR on the i.MX RT1062: Configuration and Verifying Max Speed

How I configured FlexSPI for a Winbond W25Q128JV, measured 518 Mbps read (97% of theoretical), and why the write measurement that looked great was actually a bug in my busy-poll loop.

July 25, 2026 · 9 min · 1856 words · Hoa Nguyen