I’m working on a project to control a display using an 8-bit parallel RGB interface with the Nucleo-F411RE, requiring a 1 MHz PCLK. Since the STM32F411RE lacks LTDC peripherals, I implemented the interface using a 1 MHz timer interrupt and GPIO for data transmission. However, the system fails at 1 MHz, and the UART stops working entirely—no data is transmitted or received. At lower frequencies, such as 10 KHz, the UART and other peripherals function normally.

I’m using TIMX with a system clock of 100 MHz, and GPIO handling is done via [direct register manipulation/HAL functions]. Is it possible to implement this interface on the STM32F411RE without LTDC peripherals? If so, how can I optimize it, potentially using DMA? Or should I switch to a model with LTDC support?