User`s manual

7.1.2.User Boot mode

A Note on Mats:

The H8SX/1582 possesses two distinct areas of Flash, User MAT (768KByte) and User Boot MAT (8KByte). The User Boot MAT is a

separate area of FLASH from User MAT, intended to hold user boot code.

A custom boot stub could be programmed into User Boot MAT which allows programming and erasing of the User MAT in User Mode,

without erasing the contents of the User Boot MAT. Once User Boot Mode is entered, code contained in the User Boot MAT is executed.

This differs to Boot mode, as Boot mode erases all User MAT and requires an auto-baud on a fixed SCI port to be performed. The

existence of the User Boot Mat therefore allows an alternative communications port to be used for further code download to the User MAT.

Programming of the User Boot Mat may only be performed in boot mode.

The user may place the H8SX/1582 device provided on a CPU board for the H8SX1582 board in user boot mode by fitting jumper J13. The

Boot procedure must then be performed for entry into user boot mode. The Boot LED should light, suggesting a transition to user boot

mode.

The user boot mode settings for this CPU board are shown in Table 7-3 below:

FDT Settings MD1 MD0 LSI State after Reset End

A B

0 1 User Boot Mode 1 1

Table 7-3: Mode pin settings