Software interface

PM0083

10/13

DocID018532 Rev 3

2.6

Verify the status of the option bytes

2.6.1

Programming mode entry

Follow the steps described in Section 2.4: Programming mode entry on page 7.

2.6.2

‘Option write verify’

Option write verify is a more stringent test to check the option status. It is good practice to

perform both Option read and Option write verify and compare the results in order to prove

that the options have been programmed correctly.

Table 8. Option write verify procedure

Step

Action

Description

1.

Write 0x40

0x40 is the command to be given before writing data.

2.

Write 0x0A

0x0A is the address to write data to for option status enquiry.

3.

Write 0x8i (i = 0, 1 or2)

Send the option byte number ( i ) ORed with instruction 0x80.

4.

Write 0x40

0x40 is the command to be given before writing data.

5.

Write 0x0A

0x0A is the address to write data to for option status enquiry.

6.

Write 0x9i (i = 0, 1 or 2)

Send the option byte number ( i ) ORed with instruction 0x90.

7.

Write 0x40

0x40 is the command to be given before writing data.

8.

Write 0x0A

0x0A is the address to write data to for option status enquiry.

9.

Write 0x0i (i = 0, 1 or 2)

Send the option byte number.

10. Write 0x30

0x30 is the command to be given before reading data from a RAM

address of the STM8T143.

11. Write 0x0B

0x0B is the option data address.

12. Read from device

Read option data (one byte) for this option byte.

13.

Repeat steps 1 to 12 for

option bytes 1 and 2.

Each option byte's status (for 8 option bits) is read in the same

manner.

Note: Option bytes are read in the following order: byte0, byte1 and

byte2.

14. Device power OFF

VDD = 0 V