[A83] Re: ASM program space alocation
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[A83] Re: ASM program space alocation
Hi,
the out function:
ld a,5 ;load the value 1 in a
out (a),1 ;output 1 to port 5
the in function:
well, something similar. I forgot...
Here is Dan's e-mail about ports:
----- Original Message -----
From: Dan Englender <dan@calc.org>
To: <assembly-83@lists.ticalc.org>
Sent: Monday, February 11, 2002 6:53 PM
Subject: [A83] Re: SE port 0A
>
> I posted this to the TI-H list some number of months ago, maybe it will
help
> you since you seem to be interested in the hardware. I've actually
figured
> out a good deal of information since then so some of this is out of
date...
>
> On the 83P, the following ports are used: 0,1,2,3,4,5,6,7,10h,11h,14h,16h
> Functions:
> 0 - link port
> 1 - keyboard port
> 2 - hardware stuff (low battery indicator, etc).
> 3 - Power and interrupt enable
> 4 - Interrupt speed and type
> 5 - unknown
> 6 - memory bank0 page
> 7 - memory bank1 page
> 10h - LCD instruction port
> 11h - LCD data port
> 14h - Flash lock/unlock port
> 16h - unknown
> .....You may be wondering how I know these are the only used ports. Well,
> TIOS outputs to all these ports, plus, all other ports seem to be
"shadows"
> of currently existing ports.
>
> On the SE: All ports between 0-3Fh are either zero, or have some value.
> Every port 40h-0FFh is set to 0FFh. Thus all usable ports must be in the
> 00-3Fh, though that's no guarantee that *all* ports in this range are
used).
> 0 - link (direct line access)
> 1 - keyboard
> 2 - hardware version type, battery status, etc
> 3 - Power and interrupt enable
> 4 - Interrupt type and speed
> 5 - unknown (seem to behave different than 83P though)
> 6 - memory bank0
> 7 - memory bank1
> 8 - unknown (probably something to do with link port though)
> 9 - link port hardware assist status
> Ah - link hardware assist input
> Bh/Ch - unsure, but probably link hardware assist input buffer
> Dh - link hardware assist output
> Eh/Fh - unknown, initialized to zero by TIOS and never again used
> 10h - LCD instruction
> 11h - LCD data
> 12h - appears to be a shadow of 10h
> 13h - unknown, not used by TIOS at all
> 14h - Flash lock/unlock
> 15h - unknown, when read returns a value of 33h
> 16h/17h - unknown, not used by TIOS at all
> 18h-1Fh - seem to be a hardware interface to help with MD5 routines
> 20h - bit0 = select CPU speed, bit1 = unknown. Other bits not used
> 21h-26h - unknown, initialized to values by boot page, never used again.
> Can't change values with an output to the port
> 27h-2Fh - unknown, have default values, values can be changed with no
> noticeable effect, except port 29h, where if bit4 is reset, the calculator
> crashes.
> 30h-37h - hardware timers
> 38h-3Fh - unknown, not used by TIOS at all.
>
> -Dan Englender
>
> ----- Original Message -----
> From: "Tijl Coosemans" <tijl@ulyssis.org>
> To: <assembly-83@lists.ticalc.org>
> Sent: Monday, February 11, 2002 12:03 PM
> Subject: [A83] SE port 0A
>
>
> >
> > Does reading port 0Ah automatically reset the link assist or
> > something, so it can receive a new byte? Or is this port overwritten
> > when a new byte arrives?
> >
> > Anyone an idea about what ports 0B and 0Ch do? Extra buffers maybe?
> >
> >
>
>
References: