Fair enough.  I've not had hobby time to use the little PICs for a=20
while.  Mostly PIC24 and PIC32 with C.  Efficiency isn't in that vocabulary=
..

Bill


On 3/6/2017 7:03 PM, Dwayne Reid wrote:
> Hi there, Bill.
>
> Two reasons: speed and code size.  Being able to use the TRIS
> instructions means that I don't have to spend time changing RAM banks.
>
> Don't get me wrong - I routinely control the DDR register bits from
> RAM Bank 1 when I need to.  But for either simple stuff or speedy
> stuff where I can tolerate all of the DDR bits being changed for a
> particular port, the TRIS instruction gives me significant savings.
>
> dwayne
>
>
> At 01:25 PM 3/6/2017, William Bross wrote:
>> Dwayne,
>>
>> Any special reason you just don't want to write directly to the TRISx
>> register?  The old TRIS command was really only meant for the baseline
>> stuff, where 5 - 7 are ports A - C.  Not being critical here, just curio=
us.
>>
>> Bill
>>
>>
>> On 3/6/2017 2:13 PM, Dwayne Reid wrote:
>>> Hi there, Richard.
>>>
>>> I'll give this a try.
>>>
>>> I must confess: when I saw that the TRIS operands of 5..7 didn't
>>> match up with the actual register addresses of 0x0C..0x0E, I stopped
>>> and didn't give it a try.
>>>
>>> My code does things like:
>>>
>>>        movlw  b'0011001100'
>>>        tris   RA
>>>
>>> where RA is defined as the address of port register RA
>>>
>>> The assembler complained that address 0x0C wasn't in the range of 5..7
>>>
>>> I guess that what you are saying is that the TRIS operand doesn't
>>> have to match the port register address.  I'll give that a try.
>>>
>>> I'll let you know how the actual chip behaves.
>>>
>>> Many thanks!
>>>
>>> dwayne
>>>
>>>
>>> At 02:23 AM 3/5/2017, Richard wrote:
>>>
>>>> Dwayne,
>>>>
>>>> I tried that with MPLAB IDE v8.85 (uses mpasmwin.exe v5.45) and it
>>>> worked okay.
>>>>
>>>> The test code I used is:
>>>>
>>>> #include    "p16f1782.inc"
>>>>
>>>>        MOVLW   B'00111000' ;Set RA<5:3> as inputs
>>>>        TRIS    5                           ;set TRISA to value in W
>>>>        end
>>>>
>>>> Build was successful and simulator showed expected results.
>>>>
>>>> Richard
>

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