PRELIMINARY

Erase Algorithm

Figure 3±5. Erase Algorithm Flow

 

Start

 

 

(all words=0000h)

 

 

Set VER1

 

 

bit in SEG_CTR

 

 

Wait for

 

 

td(BUSY-VERIFY)

Verify

 

 

erase

 

Read all locations

 

 

using address

 

 

complementing

 

 

Clear all bits

 

 

in SEG_CTR

 

 

All

Yes

 

words =

 

 

 

FFFFh

 

 

?

Set VER0 and

 

 

 

No

VER1 bits in

 

SEG_CTR

 

 

 

Apply one

 

 

erase pulse

Wait for

 

to flash array

 

td(BUSY-INVERSE)

 

(see Table 3±2)

 

 

Depletion

 

 

Read first

 

Erase

32 words

No

 

pulse count

 

 

 

Max² ?

 

 

 

 

No

All

 

 

Yes

 

32 words

 

 

 

 

= 0000h?

² See the device data sheet for

 

 

 

 

 

Yes

 

 

Depletion

 

the timing parameter values.

Device failure

Program array

recovery

PRELIMINARY

Algorithm Implementations and Software Considerations

3-13

Page 47
Image 47
Texas Instruments TMS320F20x/F24x DSP manual ±5. Erase Algorithm Flow