W921C840
Description
The W921E840A/W921C840 is single-chip CMOS 4-bit microcontroller that is subset of W921E880A/W921C880.
Key Features
- Operating Voltage
- 2.8 to 5.5V operating voltage for W921E840A EPROM Type
- 2.4 to 5.5V operating voltage for W921C840 Mask ROM Type Operating Frequency
- Crystal or RC for main system clock
- Crystal for 400 K, 800 K, 2 M, 3.58 M, 4 MHz - RC up to 4 MHz Memory
- 8K × 10-bit ROM (super EPROM)
- 512 × 4-bit RAM
- 64 × 4-bit special registers - 16 × 4-bit working registers - 128 × 4-bit general registers - 304 × 4-bit multi-purpose registers Stack
- 8-bit stack pointer I/O Pins
- 20 bidirectional and individually controllable I/O lines
