W921C880
Description
The W921E880A/W921C880 are 4-bit micro-processor fabricated by CMOS process. With a single channel DTMF generator, an 8-bit D/A converter circuit, a built in four by one channel comparator circuit and four multi-function timers.
Key Features
- ROM (Super EPROM): 8K × 10 bits
- RAM: 1536 × 4 bits - 64 × 4 bit Special registers - 16 × 4 bit Working registers - 128 × 4 bit General registers - 304 × 4 bit Multi-purpose registers4 bit serial buffer registers - 512 × 4-bit × 2 banks Dual-clock Operation
- Crystal or RC for the main system clock: RC up to 4 MHz Crystal for 400 K, 800 K, 2 M, 3.58 M, 4 MHz
- Crystal for subsystem clock: 32.768 KHz I/O Pins
- 32 bidirectional and individually controllable I/O lines: - P0 Port: P0.0-P0.3 large drive current Pins - P1 Port: P1.0-P1.3 large drive current Pins - P2 Port: P2.0-P2.3 large sink current pins and open drain option - P3 Port: P3.0-P3.3 multi-function I/O - P4 Port: P4.0-P4.3 open drain and pull high resistor option, multi-function I/O - P5 Port: P5.0-P5.3 multi-function I/O - P6 Port: P6.0-P6.3 open drain and pull high resistor option, multi-function I/O - P7 Port: P7.0-P7.3 large sink current pins and open drain option
- 32 bidirectional I/O lines: - P8 Port: P8.0-P8.3 large drive current pins - P9 Port: P9.0-P9.3 large sink current pins and open drain option Publication Release Date: July 1999 -3- Revision A3
