SAB88C166 Datasheet, PDF (24/58 Pages) Siemens Semiconductor Group – 16-Bit CMOS Single-Chip Microcontrollers with/without oscillator prescaler with 32 KByte Flash EPROM

SAB 88C166(W)
Flash Erase Example
This example describes the Flash erase algorithm. The four banks of the Flash memory can be
erased separately. The algorithm erases the Flash memory bank, which is selected by bitfield BE in
the FCR. Start address and size of the selected Flash bank have to be considered.
Note: Before a bank can be erased, all its contents must be programmed to ‘0000_H’. This is
required by the physics of the Flash memory cells and is done with the Flash programming
algorithm already described.
Figure 8
Memory Banking for Flash Erasure
The FCR has been defined with an EQU assembler directive. Accesses to bits of the FCR are made
via an auxiliary GPR, as the FCR itself is not bit-addressable.
The shown example uses the following assumptions:
q Pin V_PP/EBC1 receives a proper V_PP supply voltage.
q The SAB 88C166(W) runs at 20 MHz CPU clock (absolute time delays refer to it).
q The Flash memory is mapped to segment 1. All DPPs are set correctly.
Semiconductor Group
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