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You might try biscuits or dowels
1. PIC16F877 pin functions order in pin name
There is no "order of functions" for pins. Pins that are configurable usually have a "default" configuration, and then you can use the control registers to select an alternate function. So in your example, the pin is named RA2, it probably defaults to GPIO and has alternate functions as analog input 2 or VREF. There is no "order" there, which one it is depends on which configuration you select.Usually in naming they are given as:[Name]/[Alternate /[Alternate /.../[Alternate N]The order that they appear on a symbol is completely up to the person creating that symbol but is usually the same as the data sheet, although some will just put the name (ie RA2) and some may have them in different order. They are the same pin if they have the same name though (you should not have 2 pins with RA2 in them, but you may have 2 pins with AN2)
2. Why PMOS act like "close switchâ when zero voltage
You are confused because the Vg voltage COMPARED TO "ground" (or the bottom, negative power supply rail) is zero, but compared to the source pin, it is actually negative few volts (Vgs = -x volts), and a P-channel MOSFET conducts or is turned on when the gate pin is a negative few volts (usually around -3V to -10V). The text mentions the gate "voltage" (the correct term here would be "potential"), but it refers to it as relative to the ground (or the negative power supply rail) instead of to the MOSFETs source electrode, and that's where all the confusion is coming from. It's really not your fault, but the fault of the person explaining it. It is possible that the author of that schematic and the related text/explanation does not understand it well him/herself.Your schematic symbol for PMOS is flipped around - the arrow is supposed to be connecting on the Source side (to the left). It would help you to use an NMOS transistor as an example to understand the switching action. As you probably know, when the gate pin of an NMOS (N-channel MOSFET) transistor is positive compared to the source pin (also known as Vgs or gate-to-source voltage), the transistor will start conducting (a current will start flowing from drain pin to source pin). Normally you need a few volts for Vgs to turn a MOSFET on, most often around 10V and 5V for logic-level MOSFETs, even less for special types, but usually never more than 20V as that would damage most MOSFET gates. If you drop the voltage between gate and source to zero (Vgs=0V), the transistor will not conduct, it will be off. Now all you need to do is flip the polarities around, and you will understand how a P-channel MOSFET works. Do not worry if it takes you a few times to digest and understand, it is not always easy to wrap our heads around some things, even if they seem simple once we understand them.
3. Wedding flowers.. help?
I made my own boutineers for my wedding. I went and purchased white roses, just what i choose, you can choose the flower that you wish to have. You will need to proved a boutineer for the father of the bride and groom, and if your have a ring bearer. I then got some clasp pins, the kind you would see on a broach or pin, instead of using the stick pens, i did not want anyone hurt trying to pin on a boutineer. I cut them with wire cutters, I left extra and folded up, to give it a more flat look so that I could attach the clasp to it. Then I took floral tape and wrapped the stem and the pin onto it. Then I took ribbon, the colors we choose and tied them around. They looked awesome. For my bouquet, I found some already pre-made roses at Michaels. They had a few other choices. You can also google silk wedding bouquets, and you can pick out what you like from a pre-made section. I did not order online cause I wanted to see what they looked like. We got "real" flowers for the moms and grandmothers, it was easier to do this than to make them, I did not have time. But I went to the grocery store and they were pretty for a fraction of the cost of a florist. Then my mom was not able to come to my wedding, I carried a long stem rose (real). As my dad was walking me down the aisle, I stopped at the pew where my mom would be sitting and placed in on the pew and walked back to my dad and proceeded with the ceremony, I wish someone caught a picture of that but they did not . For our center pieces we used real flowers, I dunno where they got them because one of the ladies at the church who did our decorations took care of it. My guess would be that they came from the grocery store or walmart, again another cheap way to do real flowers. As far as your bouquet, my suggestion is to go with white roses and have it tied with a black ribbon. Or go with red roses and have it tied with either a white ribbon or black. Hope this helps.