W78ERD2_07 Datasheet, PDF (3/76 Pages) Winbond – 8-BIT MICROCONTROLLER

W78ERD2/W78ERD2A
1. GENERAL DESCRIPTION
The W78ERD2 is an 8-bit microcontroller which is pin- and instruction-set-compatible with the
standard 80C52. The W78ERD2 contains a 64-KB Flash EPROM whose contents may be updated in-
system by a loader program stored in an auxiliary, 4-KB Flash EPROM. Once the contents are
confirmed, it can be protected for security.
The W78ERD2 also contains 256 bytes of on-chip RAM; 1 KB of auxiliary RAM; four 8-bit, bi-
directional and bit-addressable I/O ports; an additional 4-bit port P4; three 16-bit timer/counters; and a
serial port. These peripherals are all supported by nine interrupt sources with 4 levels of priority.
The W78ERD2 has two power-reduction modes: idle mode and power-down mode, both of which are
software-selectable. Idle mode turns off the processor clock but allows peripherals to continue
operating, while power-down mode stops the crystal oscillator for minimum power consumption.
Power-down mode can be activated at any time and in any state without affecting the processor.
2. FEATURES
• 8-bit CMOS microcontroller
• Pin-compatible with standard 80C52
• Instruction-set compatible with 80C52
• Four 8-bit I/O ports; Port 0 has internal pull-up resisters enabled by software.
• One extra 4-bit I/O port with interrupt and chip-select functions
• Three 16-bit timers
• Programmable clock out
• Programmable Counter Array (PCA) with PWM, Capture, Compare and Watchdog functions
• 9 interrupt sources with 4 levels of priority
• Full-duplex serial port with framing-error detection and automatic address recognition
• 64-KB, in-system-programmable, Flash EPROM (AP Flash EPRAOM)
• 4-KB auxiliary Flash EPROM for loader program (LD Flash EPROM)
• 256-byte on-chip RAM
• 1-KB auxiliary RAM, software-selectable
• Software Reset
• 12 clocks per machine cycle operation (default). Speed up to 40 MHz.
• 6 clocks per machine cycle operation set by the writer. Speed up to 20 MHz.
• 2 DPTR registers
• Low EMI (inhibit ALE)
• Built-in power management with idle mode and power down mode
• Code protection
• Packages:
— Lead Free (RoHS) DIP 40: W78ERD2A40DL
— Lead Free (RoHS) PLCC 44: W78ERD2A40PL
— Lead Free (RoHS) PQFP 44: W78ERD2A40FL
Publication Release Date: February 14, 2007
-3-
Revision A10