I'm writing a new bios for an x86 processor with an integral SDRAM controller. I have it working with the SDRAM, but I'm troubled by a specification in the SDRAM datasheet that requires a precharge of all banks to be issued upon powerup.
As far as I can see, there is no way to run a specific SDRAM "command". Will a write to all banks accomplish the precharge?
This information is sometimes hidden away, usually near the MRS command and data register.
A write is not the same as a precharge (look carefully at the commands
- if you don't have a datasheet, go to this page for a typical SDRAM from Micron:
Do you have a link to the specific device you are using? That might enable us to help.
Cheers
PeteS
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