AN2400 Freescale Semiconductor / Motorola, AN2400 Datasheet - Page 13

• Manufacturer Part Number: AN2400
• Description: HCS12 NVM Guidelines
• Manufacturer: Freescale Semiconductor / Motorola

Flash Memory
Introduction
MOTOROLA
As soon as the running command has completed, the new command is started
with the new address and data. The command state machine is then ready to
accept the next command, as indicated by the CBEIF bit being set again, as in
Figure 12. NVM Command
The completion of the command is indicated by the CCIF bit being set. The
CCIF bit is set only when all active and pending commands for the Flash or
EEPROM block have been completed. The Flash or EEPROM block cannot be
read when the CCIF bit is clear.
Non-volatile Flash memory is used to store the application program code and
constant data. Once programmed, the Flash memory retains the code until it is
erased and reprogrammed. Flash memory can be erased and reprogrammed
many times over, refer to the microcontroller Electrical Specifications for
current data retention and write/erase endurance figures
Freescale Semiconductor, Inc.
For More Information On This Product,
Status Register
Status Register
0 0 0 0 0 0 0 0
1 1 0 0 0 0 0 0
Go to: www.freescale.com
HCS12 NVM Guidelines
Figure 15
Command State Machine
Command State Machine
Figure 16. NVM Command Complete
Command Register
Command Register
Control
Control
Running
Idle
$20
$20
.
Running.
Pipelined Command Launch
Address
Address Register
Address Buffer
Address
Address Bus
NVM
Address Bus
NVM
Address+1
Address
Address
Address
Data Register
Data
Data Buffer
Data
Data Bus
Data Bus
Data+1
Data
Data
Data
Flash Memory
AN2400/D
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