Subject: Re: more on the 400-series utility chip
To: mike smith <>
From: Herb Peyerl <>
List: port-hp300
Date: 03/21/1997 06:35:04
mike smith <>  wrote:
 > Jason Thorpe wrote:
 > > 
 > > We have the following items (offsets from util chip base)
 > ... 
 > >         0x0080          calendar of some sort
 > This one's a bit weird; have to keep looking at it.

I don't think you're terribly interested in that calendar 'cuz there's no
battery hooked up to it.

The "docs" that I have from the Apollo DN2500 (codenamed "frodo") and the 
"utility chip" that it has indicate effectively what you guys are seeing
as far as layout.

I have:
    sio0	base+0x0    keyboard/mouse
    sio1	base+0x20
    sio2	base+0x40
    sio3	base+0x60
    calendar	base+0x80   calendar / RAM device (?)
    timer       base+0xa0
    cpu_isr     base+0xc0   interrupt status reg
                bit 7     PC/AT IO_CH_CK    low = PC AT board asserted IO check
                bit 6     unused
                bit 5     53c90 scsi interrupt.
                bit 4     53c90 DMA request.
                bit 3     AT IRQ 12,none,14 or 15.
                bit 2     AT IRQ 7,9,10,11
                bit 1     AT IRQ 3,4,5,6
                bit 0     normal/service switch.   hi=normal, low=service.
    cpu_ccr     base+0xd0   cpu control reg
    diag_cr     base+0xd0   Diagnostic mode control register
                bit 7     fpu enable
                bit 6     toggle parity value when bit 5 is low
                bit 5     force parity error
                bit 4     clear parity error & buserr reg
                bit 3     enable 4mbit drams, hi=1mbit, lo=4mbit
                bit 2     disable parity error nmi.
                bit 1     margin power supply low
                bit 0     margin power supply high
    pic         base+0xe0