MC9RS08KA8RM Datasheet, PDF (35/190 Pages) Freescale Semiconductor, Inc – MC9RS08KA8 Features

Chapter 4 Memory
4.6 Flash
The flash memory is for program storage. In-circuit programming allows the operating program to be
loaded into the flash memory after final assembly of the application product. You can program the entire
array through the single-wire background debug interface. Because the device does not include on-chip
charge pump circuitry, external V_PP is required for program and erase operations.
4.6.1 Features
Flash memory features include:
• Up to 1000 program/erase cycles at typical voltage and temperature
• Security feature for flash
4.6.2 Flash Programming Procedure
Flash memory is programmed on a row basis. A row consists of 64 consecutive bytes starting from
addresses $2X00, $2X40, $2X80, or $2XC0. To program a row of flash memory:
1. Apply external V_PP.
2. Set the PGM bit. This configures the memory for program operation and enables the latching of
address and data for programming.
3. Write any data to any flash location via the high-page-accessing window $00C0–$00FF, within the
address range of the row to be programmed. (Prior to the data writing operation, the PAGESEL
register must be configured correctly to map the high-page-accessing window to the corresponding
flash row.)
4. Wait for a time, t_nvs.
5. Set the HVEN bit.
6. Wait for a time, t_pgs.
7. Write data to the flash location to be programmed.
8. Wait for a time, t_prog.
9. Repeat steps seven and eight until all bytes within the row are programmed.
10. Clear the PGM bit.
11. Wait for a time, t_nvh.
12. Clear the HVEN bit.
13. After time, t_rcv, the memory can be accessed in read mode again.
14. Remove external V_PP.
This program sequence is repeated throughout the memory until all data is programmed.
NOTE
Software code executed from flash locations cannot program or erase flash
memory. To program or erase flash, commands must be executed from
RAM or BDC commands. User code must not enter wait or stop during an
erase or program sequence.
MC9RS08KA8 Series Reference Manual, Rev. 3
Freescale Semiconductor
35