AN1827 Freescale Semiconductor / Motorola, AN1827 Datasheet - Page 24

• Manufacturer Part Number: AN1827
• Description: Programming and Erasing FLASH Memory on the MC68HC908AS60
• Manufacturer: Freescale Semiconductor / Motorola

Application Note
24
Question 10
Question 11
Question 12
Question 8
Question 9
Answer 10
Answer 11
Answer 12
Answer 8
Answer 9
Can I program/erase both FLASH arrays at the same time?
No. The charge pump is shared between both arrays to minimize silicon
area and cost. Therefore, only one high voltage FLASH operation (either
program or erase) can occur at a time on the MC68HC908AS60.
The FLASH specification states that a maximum of eight page program
cycles can be done per row between erase cycles. What does this
mean?
This specification states that a row (64 bytes of eight pages) should not
be programmed more than eight times before erasing. Programming the
row in excess of eight times risks inadvertent programming of erased
bits. (This type of fault is known as program disturb.) Programming is
done on a per-page basis where eight smart programming cycles are
used typically to program eight pages, programming the entire row of 64
bytes. If further programming is required on a row after eight program
cycles, the row must be erased first before it is programmed again.
When writing eight bytes of data to one page of FLASH memory for
programming, does the order of written data matter?
No, as long as the bytes are written within a page, the data is latched for
the programming operation.
I cannot program/erase the FLASH block protect register (FLBPR).
To program or erase the FLBPR, you must apply V
Refer to
Does bus frequency affect the programming time? For example, is
programming time using 8-MHz bus frequency shorter than using 2-MHz
bus frequency?
FLASH program times using an 8-MHz bus verses a 2-MHz bus have
minimal difference.
Freescale Semiconductor, Inc.
For More Information On This Product,
Control and Block Protect
Go to: www.freescale.com
Registers.
Hi
on the IRQ pin.
MOTOROLA
AN1827