Motorola MPC533 Reference Manual page 847

shadow information is physically located in lowest numbered block and will also be located
in small block 0 if the lowest numbered block hosts a small block in the implemented
configuration.
19.3.7.3 Program Suspend
The program operation may be suspended to allow read accesses to the array. Setting the
HSUS bit in the UC3FCTL to a 1 while PE = 0, EHV = 1, and HVS = 1 forces the array
into a program suspend state. The deassertion of the HVS bit (HVS = 0) signifies that the
program operation has been successfully suspended. The HVS bit should negate within
10µs of asserting the HSUS bit.
While in program suspend mode, normal read accesses may be performed to the UC3F
array or shadow information words. Reads to the array location targeted for program return
indeterminate data since only a partial programming operation may have been performed.
The program operation may be resumed by setting HSUS = 0.
Repeated suspending of a program operation to fetch array
contents may extend the program operation. The internal
program hardware may only resume the program operation at
predefined steps of the internal program hardware sequence;
interrupting the program operation on a high frequency basis
may cause the internal program hardware to delay completion
of the current step and delay advancement to the next step of
the internal program hardware sequence.
19.3.8 Erasing
To modify the charge stored in an isolated element of the UC3F bit from a logic 0 state to
a logic 1 state, an erase operation is required. In the UC3F EEPROM, erase is a bulk
operatBlockion that affects the stored charge of all the isolated elements in an array block.
To make the UC3F module block-erasable, the array is divided into blocks that are
physically isolated from each other. Each of the array blocks may be erased in isolation or
in any combination. The UC3F array block size is fixed for all blocks in the module at 64
Kbytes and the module is comprised of eight blocks. Two of these blocks may be further
subdivided into two small blocks. Array blocks of the UC3F EEPROM that are protected
(PROTECT[M] = 1 or (SBEN[M] = 1 & SBPROTECT[M] = 1)) will not be erased. Also,
if EPEE = 0 or B0EPEE = 0, no erase voltages will be applied to the array or the block
corresponding to block 0 or small block 0 if SBEN[0] = 1.
The embedded program/erase algorithm first pre-programs all bits in blocks selected for
erase prior to actually erasing the selected blocks.
MOTOROLA
PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
NOTE
Chapter 19. CDR3 Flash (UC3F) EEPROM
UC3F Operation
19-25