AN1827 Freescale Semiconductor / Motorola, AN1827 Datasheet - Page 6

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

Application Note
Control and Block Protect Registers
6
NOTE:
When programming the FLASH, exact program time must be used to
program a page. Excessive program time can result in a program disturb
condition, in which case an erased bit on the row being programmed
becomes unintentionally programmed. Program disturb is avoided by
using an iterative program and margin read technique known as the
smart programming algorithm. The smart programming algorithm is
required whenever programming the FLASH. See
Program/Margin Read
A security feature prevents viewing of the FLASH contents.
Programming tools are available from Motorola. Contact a local Motorola
representative for more information.
Each FLASH array has two registers that control its operation, the
FLASH control register (FLCR) and the FLASH block protect register
(FLBPR). See
There are two FLASH control registers, FLCR1 and FLCR2, for
FLASH-1 and FLASH-2 arrays, respectively.
1. No security feature is absolutely secure. However, Motorola’s strategy is to make reading or
copying the FLASH difficult for unauthorized users.
•
•
Freescale Semiconductor, Inc.
Reset:
Read:
Write:
For More Information On This Product,
$FE0B — FLASH-1 control register (FLCR1)
$FE11 — FLASH-2 control register (FLCR2)
FDIV1
Bit 7
0
Go to: www.freescale.com
Figure 1. FLASH Control Register (FLCR)
Figure 1
FDIV0
6
0
Algorithm.
and
BLK1
5
0
Figure
BLK0
4
0
2.
HVEN
3
0
MARGIN
Page
2
0
ERASE
1
0
1
MOTOROLA
AN1827
PGM
Bit 0
0