mc9s12dg128: flash control registries

[HenryL]

In trying to learn how the flash in the hcs12 micro works, i found app note AN2166 which describes programming and erasing flash and eeprom memory. In the app note, it explains the use of control registries located at $00F4, $00F5, and $00F7 (FEELCK, FEEMCR, FEECTL) that are avaliable for each 2 pages of flash. However, in the documenation specific to mc9s12dg128 there is no such registries. The registries at those locatoin are reserved for the SPI block. How to I access FEELCK, FEEMCR, FEECTL?

I'm new to micros. Apologies if this is a silly quesiton.

[nandu]

Hello ...

I think you picked up the wrong Application note. You are trying to work with HCS12 MCU family, but the application note AN2166.pdf reffers to M68HC12 MCU family. Both are different families. So, we can not say that the both the families have same registers defined at same memory address. Some registers can be added or removed in to a family when compared to the other family depending on their own requirements.

FYI, HCS12 family doest not use the registers mentioned by you (FEELCK, FEEMCR, FEECTL). Instead, it has other registers which can perform similar kind of actions that those registers do.

I think you can go throw the application note AN2400/D, which gives you an idea about the Flash memories in HCS12 family. You can find this Application note in the attachment here.

AN2400.pdf

Message Edited by t.dowe on 2009-09-15 01:47 PM