[OpenBIOS] Trying to figure out what 9 means to the escc

[Programmingkid]

On Feb 25, 2016, at 3:39 AM, Hervé Poussineau wrote:

> Le 24/02/2016 21:13, Programmingkid a écrit :
>> With the below patch I can see that Mac OS 9.0 is having escc_mem_write() go to the SERIAL_CTRL case. Then to the W_CMD case. Then to the CMD_HI case. This then causes newreg to be set to the value 9. What I need to know is what is this value for. Does anyone know what it means?
> 
> Basically, you need to first select to which register you write, and then, which value you want to write to this selected register.
> 
> Here, you write to register 0 W_CMD to choose the register 9 (by register mask value 1 + Point High Command, which adds 8) [pdf page 148], which is "Master Interrupt Control" register (W_MINTR)
> Then, you write 0xc0 to the previously selected register W_MINTR; c0 is reset for channels A & B [pdf page 167]
> 
> Hervé

Thank you very much.