> To: mike@fast (Mike Hibler)
> Cc: tmac@home.glasscity.net, port-hp300@netbsd.org
> Subject: Re: HP/Apollo Question 
> From: Herb Peyerl <hpeyerl@beer.org>
> 
> The issue with the apollo keyboard is still an issue since we can't find
> the UART in I/O space that controls that connector on all 4xx's...
> 
> I can't remember where we stood on it but didn't someone suggest that
> 4xx's running HPUX had 3 uarts wired up to the serial connector on the
> back? I remember that under Domain/OS there was only 1 serial port 
> available although I heard rumor that there were actually 2... If
> it's the case that there were 3 ports under hpux and 2 under Domain/OS,
> then I guess the answer is obvious... But looking on my 400s motherboard,
> I see only a single 16550AN... So, I'm confused...
> 
Here is the pinout for the connector (from the owner's guide):

1 ground		14 SIO2_RTS
2 SIO1_TXD		15 SIO2_CTS
3 SIO1_RXD		16 SIO2_DCD
4 SIO1_RTS		17 spare
5 SIO1_CTS		18 SIO2_DTR
6 SIO1_DSR		19 SIO3_DTR
7 inline resistor	20 SIO1_DTR
8 SIO1_DCD		21 SIO3_TXD
9 SIO3_RXD		22 SIO1_RI
10 SIO3_CTS		23 SIO3_RTS
11 spare		24 spare
12 SIO2_TXD		25 SIO3_DCD
13 SIO2_RXD

It says all three run up to 19.2k baud.  This is a Domain/OS version of the
owner's guide so I guess all three were available there as well.

I think two of the port were implemented on an IO ASIC.  I'll see if I can
find where they live in IO space...