mc68hc908qz16 Freescale Semiconductor, Inc, mc68hc908qz16 Datasheet - Page 39

• Manufacturer Part Number: mc68hc908qz16
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

The address ranges for the user memory and vectors are:
Programming tools are available from Freescale Semiconductor. Contact your local representative for
more information.
2.6.2 FLASH Control Register
The FLASH control register (FLCR) controls FLASH program and erase operations.
HVEN — High-Voltage Enable Bit
MASS — Mass Erase Control Bit
ERASE — Erase Control Bit
PGM — Program Control Bit
1. No security feature is absolutely secure. However, Freescale’s strategy is to make reading or copying the FLASH difficult for
Freescale Semiconductor
unauthorized users.
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•
•
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This read/write bit enables the charge pump to drive high voltages for program and erase operations
in the array. HVEN can only be set if either PGM = 1 or ERASE = 1 and the proper sequence for
program or erase is followed.
Setting this read/write bit configures the 16-Kbyte FLASH array for mass erase operation.
This read/write bit configures the memory for erase operation. ERASE is interlocked with the PGM bit
such that both bits cannot be equal to 1 or set to 1 at the same time.
This read/write bit configures the memory for program operation. PGM is interlocked with the ERASE
bit such that both bits cannot be equal to 1 or set to 1 at the same time.
1 = High voltage enabled to array and charge pump on
0 = High voltage disabled to array and charge pump off
1 = MASS erase operation selected
0 = PAGE erase operation selected
1 = Erase operation selected
0 = Erase operation unselected
1 = Program operation selected
0 = Program operation unselected
$C000–$FDFF; user memory
$FE08
$FF7E; FLASH block protect register
$FFD4–$FFFF; these locations are reserved for user-defined interrupt and reset vectors
;
Address:
FLASH control register
Reset:
Read:
Write:
A security feature prevents viewing of the FLASH contents.
$FE08
Bit 7
0
0
MC68HC908GZ16 • MC68HC908GZ8 Data Sheet, Rev. 4
Figure 2-3. FLASH Control Register (FLCR)
= Unimplemented
6
0
0
5
0
0
NOTE
4
0
0
HVEN
3
0
MASS
2
0
ERASE
1
0
(1)
FLASH Memory (FLASH)
PGM
Bit 0
0
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