MC68F375
CDR MoneT FLASH FOR THE IMB3 (CMFI)
MOTOROLA
REFERENCE MANUAL
Rev. 25 June 03
10-3
access the required information is 2 system clocks. Reads will always begin with a 2
clock access. If the IMB3 indicates a burst access the following access(es) will be 1
clock until the CMFI reaches the end of the burst buffer or the IMB3 terminates the
burst access. During the burst reads, the CMFI increments the address by one word
each access. The end of the burst buffer is indicated by the highest location within the
burst buffer being read, ADDR[4:0] = 0x1F. All burst accesses are aligned to the IMB3
data bus, ignoring the byte address(es). To prevent the BIU from unnecessarily
accessing the array, the CMFI EEPROM shall monitor the IMB3 address to determine
if the required information is in one of the two current burst buffers and the access is
valid for the module. This process is designed to reduce power consumption by the
CMFI.
In normal operation write accesses to the CMFI array are not recognized.
The CMFI EEPROM module requires an external program or erase voltage, VPP, to
program or erase the array or any of its control register shadow bits. Special control
logic is included to require a specific series of read and write accesses before program
or erase operation is allowed.
To improve program performance, the CMFI programs up to eight unique 64-byte
pages simultaneously in eight separate array blocks. These 64 bytes are aligned to the
low order addresses, IADDR[5:0], to form a program page buffer. Each of the pages
being programmed simultaneously are located at the same block offset address,
IADDR[23:15|14]. Erase is performed on one or more of the selected array blocks
simultaneously.
10.1.2 Features of the CMFI
MOTOROLA’s 1 transistor, MoneT, FLASH bit cell.
-40 to 125
° C operating temperature range.
VDD 3. 0 V to 3. 6 V operating range.
— Operational at 2. 7 V.
— Up to 40 MHz operation at VDD = 3. 0 V, 150° C = TJ.
Shadow and bootstrap information stored in special FLASH NVM locations.
256-Kbyte array size.
Array distributed in 8 blocks.
— Erase by array block(s).
— Common array block size of 32 Kbytes.
— Array lock protection for program and erase operations.
Built-in margin reads for both program and erase verify reads.
Array access disabled while programming or erasing.
— Array address attributes restriction control.
Select between supervisor and supervisor/user spaces.
Select between data and instruction/data spaces.
Program up to 512 bytes at a time.
— Program up to eight 64-byte pages simultaneously.
— Pages located at the same offset address.
Self-timed program and erase pulses.
— Internal pulse width timing control using system clock frequencies from 8.0
F
re
e
sc
a
le
S
e
m
ic
o
n
d
u
c
to
r,
I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
n
c
..
.