P89LPC952_954_4 © NXP B.V. 2008. All rights reserved.
Product data sheet Rev. 04 — 24 July 2008 45 of 69
NXP Semiconductors
P89LPC952/954
8-bit microcontroller with 10-bit ADC
7.26.5 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.
7.26.6 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
P89LPC952/954 through a two-wire serial interface. The Philips 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 P89LPC952/954
User’s Manual
.
7.26.7 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 Philips 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 P89LPC952/954
User’s Manual
.
7.26.8 ISP
ISP is performed without removing the microcontroller from the system. The ISP facility
consists of a series of internal hardware resources coupled with internal firmware to
facilitate remote programming of the P89LPC952/954 through the serial port. This
firmware is provided by Philips and embedded within each P89LPC952/954 device. The
Philips ISP facility has made in-system programming in an embedded application possible
with a minimum of additional expense in components and circuit board area. The ISP
function uses five pins (V
DD
, V
SS
, TXD, RXD, and RST). Only a small connector needs to
be available to interface your application to an external circuit in order to use this feature.
