DR
AFT
DR
AFT
DRAFT
DR
D
RAFT
DRAFT
DRA
FT DRAF
D
RAFT DRAFT DRAFT DRAFT DRAFT D
DRAFT
D
RAFT DRA
FT DRAFT DRAFT DRAFT DRA
UM10316_0
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 00.06 — 17 December 2008
486 of 571
NXP Semiconductors
UM10316
Chapter 28: LPC29xx Flash/EEPROM
If the read data register is read while the read operation is still pending, then the read
transfer on the system bus is stalled by de-asserting the ready signal until the previous
read operation is finished. This can be avoided by polling the interrupt status register to
see if the operation is still pending before reading the read data register.
By default read operations will automatically post-increment the address register. This
allows consecutive reads from the EEPROM memory without the need of writing a new
address for every read operation. By setting the read data pre-fetch bit in the command
register reading from the read data register automatically starts up a read operation from
the next (incremented) address location. When doing consecutive reads in this way the
first read operation is started as result of writing the command register. The following read
operations are started as result of reading the read data register to obtain the result of the
previous read operations.
Read operations from a misaligned address will result on an error response on the write
transfer to the command register (for example a 32-bit read operation from an address
other than a multiple of 0x4). The operation will not be performed.
2.10.4 Error responses
The controller can generate the following EEPROM related error responses in the
following situations:
•
An erase/program operation on the protected page will result in an error response on
the write transfer to the command register.
•
Writing a read-only register or reading a write-only register will result in an error
response.
•
A transfer to a non-existing register location will result in an error.
2.10.5 EEPROM usage note
The minimum operating voltage for the data EEPROM is V
dd
= 1.5 V.
3.
FMC register overview
The Flash Memory Controller registers have an offset to the base address FMC RegBase
which can be found in the peripherals base-address map, see
.
Fig 126. Starting a read operation (read from address A)
write address register
(address A)
write command register
operation on
E E P R O M
now starts
read readdata register