W78E54-16 Winbond, W78E54-16 Datasheet - Page 3

• Manufacturer Part Number: W78E54-16
• Description: 8-BIT MICROCONTROLLER
• Manufacturer: Winbond

PIN DESCRIPTION
The W78E54 has two operating modes, normal and flash. In normal mode, the W78E54 corresponds
to the W78C54. In flash mode, the user (the maker of the flash EEPROM writer) can access the flash
EEPROM.
P0.7 P0.0 Port 0, Bits 7 0
P1.7 P1.0 Port 1, Bits 7 0
P2.7 P2.0 Port 2, Bits 7 0
P3.7 P3.0 Port 3, Bits 7 0
P4.3 P4.0 Port 4, Bits 3 0 (available on 44-pin PLCC/QFP package)
Normal
Normal
Normal
Normal
Normal
MODE
MODE
MODE
MODE
MODE
Flash
Flash
Flash
Flash
Port 0, Bits 0 through 7. Port 0 is a bidirectional I/O port. This port also provides a
multiplexed low order address/data bus during accesses to external memory.
This port provides the data bus during access to the flash EEPROM.
Port 1, Bits 0 through 7. Port 1 is a bidirectional I/O port with internal pull-ups. Pins
P1.0 and P1.1 also serve as T2 (Timer 2 external input) and T2EX (Timer 2
capture/reload trigger), respectively.
This port provides the low-order address bus during access to the flash EEPROM.
Port 2, Bits 0 through 7. Port 2 is a bidirectional I/O port with internal pull-ups. This port
also provides the upper address bits for accesses to external memory..
This port provides the high-order address bus during access to the flash EEPROM.
Port 3, Bits 0 through 7. Port 3 is a bidirectional I/O port with internal pull-ups. All bits
have alternate functions.
P3.3 P3.0 and P3.7 P3.6 are the flash mode configuration pins, Input.
P3.3 P3.0 and P3.7 P3.6 are configured to select or execute the flash operations. For
details, see Flash Operations.
Another bit-addressable bidirectional I/O port P4. P4.3 and P4.2 are alternative
function pins. It can be used as general I/O pins or external interrupt input sources
( INT2 / INT3 ).
DESCRIPTION
DESCRIPTION
DESCRIPTION
DESCRIPTION
DESCRIPTION
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Publication Release Date: November 1997
W78E54
Revision A2