Texas Instruments MSP50C614 manual Block Protection Word, Write only

Models: MSP50C614

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Memory Organization: RAM and ROM

The protection modes are implemented on the C614 as follows. Within the ROM is a dedicated storage for the block protection word (address 0x7FFE). The block protection word is divided into two 6-bit fields and two single-bit fields. The remainder of the 17-bit word is broken into three single-bit fields which are reserved for future use.

ROM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Block Protection Word

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

address 0x7FFE

(17-bit wide location)

 

 

 

 

 

 

 

 

 

 

 

 

 

WRITE only

16

15

14

13

12

11

10

09

08

07

06

05

04

03

02

01

00

 

R

R

TM

TM

TM

TM TM

TM

GP

BP

R

FM FM FM FM FM FM

 

 

 

05

04

03

02

01

00

 

 

 

05

04

03

02

01

00

TM :

True Protection Marker (NTM)

GP : Global Protection (0 value protects)

FM :

False Protection Marker (NFM)

BP : Block Protection (0 value protects)

R :

Reserved for future use (must be 1)

1 : Default value of cells on erasure

The two 6-bit fields are designated as the true protection marker, (TM5 through TM0) and the false protection marker, (FM5 through FM0). When setting up a partition for partial ROM protection, the address of the partition must be spe- cified as:

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Texas Instruments MSP50C614 manual Block Protection Word, Write only