Specifications

FC protocol, version 3, large M68HC08 implementation
Developer’s Serial Bootloader, Rev. 13
Freescale Semiconductor 23
5 FC protocol, version 3, large M68HC08
implementation
This section describes features specific to the protocol version 3 of the bootloader. This is intended for
large HC08s (with two or more FLASH memory banks or, more precisely, with two or more separated
FLASH memory areas). The format of the Ident command from version 2 is used; the rest remains same
as with protocol version 1 (HC08) namely Interrupt vector table relocation.
6 FC protocol, version 4, ColdFire (V1)
The protocol version 4 is divided into two versions, version A and version B. The main reason for this
separation is the possibility of protecting the bootloader source code. This feature is important for flash
programming because protection of the bootloader prevents the source code from being erased. The
implementation of version A bootloader is not protected where as the version B implementation is
protected.
6.1 Version A (unprotected version)
This section describes the features that are specific to Cold Fire V1 implementation version A. The
memory allocation is MCU specific, so the meaning of all variables is explained in this section.
Figure 18 shows the memory allocation typical to the ColdFire V1 devices with the bootloader
preprogrammed. For example, the MCF51JM128 device memory map includes:
• 128 KB of FLASH memory ($00000000-$0001FFFF)
• 16 KB of random access memory (RAM) ($00800000-$00803FFF)
• 16 bytes of nonvolatile registers ($00000400-$0000040F)
• 444 bytes of user-defined vectors ($00000000-$000001B8)