P89C668 Philips Semiconductors, P89C668 Datasheet - Page 43

• Manufacturer Part Number: P89C668
• Description: 80C51 8-bit Flash microcontroller family 64KB ISP FLASH with 8KB RAM
• Manufacturer: Philips Semiconductors

Philips Semiconductors
FLASH EPROM MEMORY
GENERAL DESCRIPTION
The P89C668 Flash memory augments EPROM functionality with
in-circuit electrical erasure and programming. The Flash can be read
and written as bytes. The Chip Erase operation will erase the entire
program memory. The Block Erase function can erase any Flash
byte block. In-system programming and standard parallel
programming are both available. On-chip erase and write timing
generation contribute to a user friendly programming interface.
The P89C668 Flash reliably stores memory contents even after
1000 erase and program cycles. The cell is designed to optimize the
erase and programming mechanisms. In addition, the combination
of advanced tunnel oxide processing and low internal electric fields
for erase and programming operations produces reliable cycling.
The P89C668 uses a +5 V V
Program/Erase algorithms.
FEATURES – IN-SYSTEM PROGRAMMING (ISP)
AND IN-APPLICATION PROGRAMMING (IAP)
2001 Jul 27
Flash EPROM internal program memory with Block Erase.
Internal 1 kbyte fixed boot ROM, containing low-level in-system
programming routines and a default serial loader. User program
can call these routines to perform In-Application Programming
(IAP). The Boot ROM can be turned off to provide access to the
full 64 kbyte Flash memory.
Boot vector allows user provided Flash loader code to reside
anywhere in the Flash memory space. This configuration provides
flexibility to the user.
Default loader in Boot ROM allows programming via the serial port
without the need for a user provided loader.
Up to 64 kbyte external program memory if the internal program
memory is disabled (EA = 0).
Programming and erase voltage +5 V or +12 V.
Read/Programming/Erase using ISP/IAP:
– Byte Programming (20 s).
– Typical quick erase times (including preprogramming time):
Parallel programming with 87C51 compatible hardware interface
to programmer.
In-system programming.
Programmable security for the code in the Flash.
1000 minimum erase/program cycles for each byte.
10 year minimum data retention.
80C51 8-bit Flash microcontroller family
64KB ISP Flash with 8KB RAM
Block Erase (8 kbytes or 16 kbytes) in 10 seconds.
Full Erase (64 kbytes) in 20 seconds.
PP
supply to perform the
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on-chip ISP boot loader may be invoked. This ISP boot loader will, in
by using a commercially available EPROM programmer. The parallel
CAPABILITIES OF THE PHILIPS 89C51
FLASH-BASED MICROCONTROLLERS
Flash organization
The P89C668 contains 64 kbytes of Flash program memory. This
memory is organized as 5 separate blocks. The first two blocks are
8 kbytes in size, filling the program memory space from address 0
through 3FFF hex. The final three blocks are 16 kbytes in size and
occupy addresses from 4000 through FFFF hex.
Figure 45 depicts the Flash memory configurations.
Flash Programming and Erasure
There are three methods of erasing or programming of the Flash
memory that may be used. First, the Flash may be programmed or
erased in the end-user application by calling low-level routines
through a common entry point in the Boot ROM. The end-user
application, though, must be executing code from a different block
than the block that is being erased or programmed. Second, the
turn, call low-level routines through the same common entry point in
the Boot ROM that can be used by the end-user application. Third,
the Flash may be programmed or erased using the parallel method
programming method used by these devices is similar to that used
by EPROM 87C51, but it is not identical, and the commercially
available programmer will need to have support for these devices.
Boot ROM
When the microcontroller programs its own Flash memory, all of the
low level details are handled by code that is permanently contained
in a 1 kbyte “Boot ROM” that is separate from the Flash memory. A
user program simply calls the common entry point with appropriate
parameters in the Boot ROM to accomplish the desired operation.
Boot ROM operations include things like: erase block, program byte,
verify byte, program security lock bit, etc. The Boot ROM overlays
the program memory space at the top of the address space from
FC00 to FFFF hex, when it is enabled. The Boot ROM may be
turned off so that the upper 1 kbytes of Flash program memory are
accessible for execution.
P89C668
Preliminary data