NEC V25 explained

The NEC V25 (μPD70320) is the microcontroller version of the NEC V20 processor, manufactured by NEC Corporation. Features include:

• NEC V20 core: 8-bit external data path, 20-bit address bus, machine code compatible with the Intel 8088 (the processor used in the original IBM PC)
• On-chip peripheral hardware mapped in memory address space
• Two-channel 16-bit timers
• Internal interrupt controller
• Dual-channel UART and baud rate generator for serial communications^[1]
• Eight register banks,^[2] base address of which can be dynamically relocated with Internal Data area Base (IDB) Register.^[3]
• A two-channel DMA controller, enabling the direct addressing of the entire 1MB memory address space.^[4]

It was officially phased out by NEC in early 2003.^[5]

Notes and References

1. Web site: User's Manual – V25, V35 – 16/8-, 16-bit Single-chip microcontrollers – Hardware . 221 . NEC Corporation . 1998.
2. Web site: User's Manual V25 V35 16/8-, 6-Bit Single-Chip Microcontrollers Hardware . 62 . 2023-11-03 .
3. Web site: User's Manual V25 V35 16/8-, 16-Bit Single-Chip Microcontrollers Hardware . 77 . 2023-12-18.
4. Web site: User's Manual V25 V35 16/8-, 16-Bit Single-Chip Microcontrollers Hardware . 173 . 2023-11-27 .
5. Web site: NEC V25 EOL . Tern inc . https://web.archive.org/web/20060913062554/http://www.tern.com/docs/V25_EOL_note.pdf . Sep 13, 2006.