SK40C questions which couldn't found in FAQ.

[dccf88]

1) I have referred to the schematic of SK40C but I'm still not understand what is the value and what is the function of Vin for Header21, JP4.

2) From the schematic showed that crystal is connected to 2 capacitors and goes to ground, but why on the SK40C, the turn pin(3 pins) of crystal is included ground? Does the ground need to connect? because it is already connected with capacitors.

3) Do I need to connect with my own 5V power supply to the Vdd of the pin 11 & 32? or once i connect DC adapter to SK40C, it will already have?

4) With using UICOOB programmer to connect with SK40C to load the program code into PIC16F877A. Does the Vin (mentioned at Q1) have to connect?

5) From Q4, if I have connected all the wires to the turn pin(port of PIC) of SK40C from my other hardwares like SKKCA-21, IR sensor and DC motor. When I want to load the program from UICOOB to my PIC, do i need to disconnect all the wires(hardwares) from the SK40C's turn pin?

[dccf88]

Anyone please?

[aurora]

If I read it correctly:

1. Vin is just a turn pin for user to check the supply voltage. Basically it has the same voltage as the supply.

2. You mean the Gnd pin on SK40C? The schematic show the Xtal is connected to pin 1&3, while pin 2 is ground. The schematic is correct, just slot the Xtal into pin1&3. Design-wise, it is not feasible to put 2 single turn pin with a gap in between. So they put a 3-piece pin and grounded the middle one. Ungrounded pin may cause noise and distort the signal, so they ground it.

3. No need to supply 5Vdd. Just plug in a voltage between 7 - 12v into the adapter socket.

4. Just connect the 7-12v supply will do. Vin is just a dummy pin.

5. UIC00B use pin39 (RB6) and pin40 (RB7). If you are using this 2 pins, disconnect it when you want to program the PIC. Other pin are not necessary.

[dccf88]

Hi Aurora,

Thank you so much for your reply.
Finally I have understood all of them

Thanks again!

[shiyan]

1) I have referred to the schematic of SK40C but I'm still not understand what is the value and what is the function of Vin for Header21, JP4.

Even after looking through schematic ? I think is very basic, it is just an extension out for user to use the input voltage, else you will not get any pin that provide it. There is only 5V and Gnd, if I want to use 12V or 9V from the input where should I take if there is not Vin pin? Referring to the schematic, Vin is voltage where adapter power after a Diode, might have some voltage drop compare to Vin from adapter.

2) From the schematic showed that crystal is connected to 2 capacitors and goes to ground, but why on the SK40C, the turn pin(3 pins) of crystal is included ground? Does the ground need to connect? because it is already connected with capacitors.

Again, I think that is being shown in schematic too and I agree with what aurora said, for the sake of easy mounting of turn (hole) pin, and the ground is just for stabilization. You can omit that.

3) Do I need to connect with my own 5V power supply to the Vdd of the pin 11 & 32? or once i connect DC adapter to SK40C, it will already have?

If you need to do some much of connection, what is the point getting the board at the first place? I started to doubt you refer to the User's Manual Seriously.

4) With using UICOOB programmer to connect with SK40C to load the program code into PIC16F877A. Does the Vin (mentioned at Q1) have to connect?

Where do you want to connect the Vin? Again, I think the User's Manual of SK40C show how to load program using the UIC, right?

5) From Q4, if I have connected all the wires to the turn pin(port of PIC) of SK40C from my other hardwares like SKKCA-21, IR sensor and DC motor. When I want to load the program from UICOOB to my PIC, do i need to disconnect all the wires(hardwares) from the SK40C's turn pin?

I think you should get the idea after the above explanation, and I really hope you really try it out. If you need to disconnect all those connections before you load program, I rather do my own board than buy few pcs of SK40C during crazy sales.

[aurora]

dccf88: No problem. Coincidentally I was checking the circuit

Cytron: In the schematic, JP1 for ICSP, wasn't Pin 8 suppose to be connected to Vdd? Still waiting for my parcel, but if anyone can confirm that will be good.

I haven't paid any attention to the board when I drop my order, it was a really good deal and got myself one of it during the crazy sales. (lol, kiasu people mah) Not to mention so many other forumers wanted this board so badly!

Anyhow, it was a quick buy and ended-up overlook the details and forget the USB-UART Converter (UC00A)! Will the USB-Serial Converter work in this case?

Any chance for a new sub-forum on product development? It is always nice to get feedback from user and further improve the package. I would like to see additional cable terminal connector for 5V input. Microcontroller circuit mainly falls on the 5v range, right?

[dccf88]

dccf88: No problem. Coincidentally I was checking the circuit

Cytron: In the schematic, JP1 for ICSP, wasn't Pin 8 suppose to be connected to Vdd? Still waiting for my parcel, but if anyone can confirm that will be good.

I haven't paid any attention to the board when I drop my order, it was a really good deal and got myself one of it during the crazy sales. (lol, kiasu people mah) Not to mention so many other forumers wanted this board so badly!

Anyhow, it was a quick buy and ended-up overlook the details and forget the USB-UART Converter (UC00A)! Will the USB-Serial Converter work in this case?

Any chance for a new sub-forum on product development? It is always nice to get feedback from user and further improve the package. I would like to see additional cable terminal connector for 5V input. Microcontroller circuit mainly falls on the 5v range, right?

Haha, I did buy UICOOB programmer but didn't buy adapter as I buy it very rush during crazy sales too. My goods will be reached by tomorrow if not misstaken.

Micro controller assumes that the voltage above 1.8V is HIGH, but the voltage within 1.8-3.4V is not stable. 3.5V-5V is very stable. Is this is the answer that you want?

[dccf88]

3) Do I need to connect with my own 5V power supply to the Vdd of the pin 11 & 32? or once i connect DC adapter to SK40C, it will already have?

If you need to do some much of connection, what is the point getting the board at the first place? I started to doubt you refer to the User's Manual Seriously.

I have understood this, for load the program source code, adapter is needed, while 5V is needed when doing interfacing like connect hardware and software.

4) With using UICOOB programmer to connect with SK40C to load the program code into PIC16F877A. Does the Vin (mentioned at Q1) have to connect?

Where do you want to connect the Vin? Again, I think the User's Manual of SK40C show how to load program using the UIC, right?

Vin is just for external use, can be used to measure the value of Vin. I hope this is correct

5) From Q4, if I have connected all the wires to the turn pin(port of PIC) of SK40C from my other hardwares like SKKCA-21, IR sensor and DC motor. When I want to load the program from UICOOB to my PIC, do i need to disconnect all the wires(hardwares) from the SK40C's turn pin?

I think you should get the idea after the above explanation, and I really hope you really try it out. If you need to disconnect all those connections before you load program, I rather do my own board than buy few pcs of SK40C during crazy sales.[/quote]

haha, ya im understand what you say.
Aurora had mentioned that for the programmer which is ICSP, the pins are Vdd, Gnd, RB6 and RB7. The rest doesn't matter.

[kl84]

Anyhow, it was a quick buy and ended-up overlook the details and forget the USB-UART Converter (UC00A)! Will the USB-Serial Converter work in this case?

The max232 chip has been taken out from SK40C design. Cytron only provides the pin holes for UART interface (for UC00A). However, from SK40C's product page i can see some usb stuff mentioned. So i think if you are using usb enabled PICs like 18F4550, you can make SK40C a CDC usb device which can communicate through usb without using UC00A. You can have a look at Microchip's usb solution.

[ober]

Cytron: In the schematic, JP1 for ICSP, wasn't Pin 8 suppose to be connected to Vdd? Still waiting for my parcel, but if anyone can confirm that will be good.

hi, thanks for support Cytron product. Glad to see you like it. Yes, pin 8 should be connected to Vdd if you would like to use the power from USB programmer. We do not encourage the power usage from programmer as it is being shared with USB and the programmer itself, not much left for project circuitry and other devices. Therefore, we disconnect it. You will need to power the SK40C from external in order to load program, that's all.

Anyhow, it was a quick buy and ended-up overlook the details and forget the USB-UART Converter (UC00A)! Will the USB-Serial Converter work in this case?

Oh.... sorry to hear that, many grab the complete package including the UC00A, UIC, UIC-S, 4550, 877A, etc. Anyway you can still use a USB to serial converter, the extra work is to add a MAX232 in between SK40C and USB to serial converter + the DB9 connector... which will take a lot of work.

Any chance for a new sub-forum on product development? It is always nice to get feedback from user and further improve the package. I would like to see additional cable terminal connector for 5V input. Microcontroller circuit mainly falls on the 5v range, right?

Sure, you are free to open a new category, just hope that more people can be active in giving feedback and sharing. As you might have noticed, our country does not have that culture and motivation. The technical forum is normally being maintained by just a few active members. Really happy to see you back here and hope to get your feedback and support.