The microcontroller used in IBM PC keyboards. The 8048 was inspired by, and similar to, the Fairchild F8 microprocessor but, being a microcontroller, was designed for low cost and small size. The 8048 has a modified Harvard architecture, with program ROM on chip and 64 to 256 bytes of RAM also on chip. I/O is mapped in its own address space.
Though the 8048 was eventually replaced by the very popular but bizarre Intel 8051 and Intel 8052, even in 2000 it is still very popular due to its low cost, wide availability, and development tools.
[Was it really __the_first__ microcontroller? Are the ROM and RAM both on-chip?]