R6504 8-Bit Microprocessor 1MHz (DIP-28)

The R6504 is a specialized 8-bit microprocessor that belongs to the renowned 6500 family, originally designed as a cost-effective alternative to the 6502. It features the same internal 32-bit register structure and instruction set as the 6502 but is housed in a smaller 28-pin DIP package. To achieve this reduced pin count, the external address bus is limited to 13 lines, providing a total memory addressing space of 8,192 bytes. This makes the R6504 an ideal choice for low-cost controller applications where a full 64KB address range is not required. It is fully software-compatible with other 6500 series processors, allowing developers to utilize existing codebases and development tools. The R6504 was widely used in early arcade games, peripherals, and small industrial controllers that demanded reliable 8-bit processing in a compact footprint.

Key Features:

Supports a total addressable memory range of 8 kilobytes.

Standard 1MHz clock frequency for reliable legacy processing performance.

Features 56 powerful instructions and 13 versatile addressing modes.

Single 5V power supply operation for simplified circuit design.

Compact 28-pin dual in-line package for space-efficient hardware layouts.