What are the differences between the original FT232H and the FT232HP?

The FT232HP offers the same functionality as the FT232H. It can be used for UART, bit bang, I2C/SPI via MPSSE, etc. The FT232HP offers additional power delivery functionality. This allows for control of power direction which can be either supplied from the USB Host or the device. The same applies to all ‘HP’ variants. The original FT232H only had the ability to get power from the USB Host.