Input type

PieM

Senior Member
On PIC18F25/15K22 Data sheet (picaxe 28X2 40X2) PortC & PortD inputs are ST type.
On manual2 (inputtype) all inputs are TTL type? what's wrong ?
 

Technical

Technical Support
Staff member
You are incorrect, see datasheet snapshot attached e.g. portC on 18F25K22 (28X2) are TTL when used as normal inputs.
 

Attachments

Dippy

Moderator
Perhaps we should include the Document reference and date when making comparisons?

My own copy (DS41412F 2010-2012) agrees with Technical for the 2xK22.
However, for the 4xK22 PortC,D & E I/O are shown as ST.

So, it may be a good idea to confirm that we are all reading the same Data Sheet.
And also the same section of the Data Sheet.
I haven't looked to see if there is a newer one with changes.
(M'chip do make boo-boos).
 

Dippy

Moderator
Same Datasheet.

Well, this is a bit confusing.
Section 10.4 (PORTC):
"The pins have Schmitt Trigger input buffers."
Ditto PORTD in Section 10.5.
And agrees in table 10.8 and 10.11 respectively.

This consistent with the earlier table 1-3 for the 4xK22, but not consistent with the table for the 2xK22 (which was posted by Technical).
I may have missed something (as my coffee is getting cold), but it looks like a Microchip have allowed a Typo to sneak through.

Maybe someone should contact Microhip? (Assuming my glasses haven't failed me).
If it isn't a mistake it's still confusing.
 

Technical

Technical Support
Staff member
From Microchip
I am in the process of updating the PIC18F1xK22 and PIC18F2x/4xK22 datasheets. This is one of the issues being fixed in those datasheets. All of the PORTC pin have Schmitt Trigger input buffers. The table 1-2 has them incorrectly listed as TTL. This is fixed in the update of the datasheet, but I am not sure when it will be released as I am still making edits.
 
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