P89LPC9351_1 © NXP B.V. 2008. All rights reserved.
Preliminary data sheet Rev. 01 — 19 November 2008 48 of 74
NXP Semiconductors
P89LPC9351
8-bit microcontroller with 8-bit ADC
7.30.4 Using flash as data storage
The flash code memory array of this device supports individual byte erasing and
programming. Any byte in the code memory array may be read using the MOVC
instruction, provided that the sector containing the byte has not been secured (a MOVC
instruction is not allowed to read code memory contents of a secured sector). Thus any
byte in a non-secured sector may be used for non-volatile data storage.
7.30.5 Flash programming and erasing
Four different methods of erasing or programming of the flash are available. The flash may
be programmed or erased in the end-user application (IAP) under control of the
application’s firmware. Another option is to use the ICP mechanism. This ICP system
provides for programming through a serial clock/serial data interface. As shipped from the
factory, the upper 512 bytes of user code space contains a serial ISP routine allowing for
the device to be programmed in circuit through the serial port. The flash may also be
programmed or erased using a commercially available EPROM programmer which
supports this device. This device does not provide for direct verification of code memory
contents. Instead, this device provides a 32-bit CRC result on either a sector or the entire
user code space.
Remark: When voltage supply is lower than 2.4 V, the BOD FLASH is tripped and flash
erase/program is blocked.
7.30.6 ICP
ICP is performed without removing the microcontroller from the system. The ICP facility
consists of internal hardware resources to facilitate remote programming of the
P89LPC9351 through a two-wire serial interface. The NXP ICP facility has made in-circuit
programming in an embedded application - using commercially available programmers -
possible with a minimum of additional expense in components and circuit board area. The
ICP function uses five pins. Only a small connector needs to be available to interface your
application to a commercial programmer in order to use this feature. Additional details
may be found in the P89LPC9351
User manual
.
7.30.7 IAP
IAP is performed in the application under the control of the microcontroller’s firmware. The
IAP facility consists of internal hardware resources to facilitate programming and erasing.
The NXP IAP has made in-application programming in an embedded application possible
without additional components. Two methods are available to accomplish IAP. A set of
predefined IAP functions are provided in a Boot ROM and can be called through a
common interface, PGM_MTP. Several IAP calls are available for use by an application
program to permit selective erasing and programming of flash sectors, pages, security
bits, configuration bytes, and device ID. These functions are selected by setting up the
microcontroller’s registers before making a call to PGM_MTP at FF03H. The Boot ROM
occupies the program memory space at the top of the address space from FF00H to
FEFFH, thereby not conflicting with the user program memory space.
In addition, IAP operations can be accomplished through the use of four SFRs consisting
of a control/status register, a data register, and two address registers. Additional details
may be found in the P89LPC9351
User manual
.
