The MPLAB Xpress board is a very powerful and versatile platform and at the current price of $12 is also great value for money.
In addition to a powerful PIC16F18855 processor the board also has a PIC18LF25K50 Device acting as a Programmer for the 16F18855, eliminating the need for a separate PICKit 3 programmer.
The PIC18LF25K50 Device is also programmed as a USB/Serial Bridge which is capable of running independently of the 16F18855 device.
So what does this mean?
It means that if you have an Xpress Evaluation Board you have the equivalent of a 15 to 20 Dollar FTDI device laying on your desk for free.
The USB bridge works independently of the 16f18855 but it does share the RC0/RC1 pins, so to avoid any possible conflict I created "The Worlds Smallest PIC Program"
RC0 (red in the image) will be the Rx for your PC and Tx for the target device
RC1 (Yellow in the Image) will be Tx from the PC and Rx to your target.
Gnd is next to the RC0 pin.
Remember this is a 3V3 device so use a level converter, or at least resistors in series, if connecting to a 5V target.
As a simple test of the system, place a jumper from RC0 to RC1, open the terminal, select the com port your XPress Board created and send "Hello World!".
So next time you are struggling to find that elusive FTDI board, just grab your ever versatile Xpress board instead.
Cheers!
Chris
Last edit: Chris Roper 2017-11-17
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Chris, I was thinking about using rb.7,rb.6 and mclr wired to another board with a "new" similar pic and use icsp instead of pickit3 and the perceived bother. daft idea? Worth trying?
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The PGC and PGD pins have not been brought out to headers so you can't use
it as a programmer.
I tried., even if you cut the boards apart you can't access them, only the
USB/Serial is available.
This one may be able to do it.
Part Number: DM164141 - MPLABXpress PIC16F18345 Evaluation Board
The programming pins are RA0 and RA1, Mclr is RA3.
All of which are brought out to the edge.
As the device is not socketed you would probably have to lift it and sacrefice the development board aspect.
On the up side you would be getting a Programmer, dual supply and USB/USART Bridge for $12.
The NSDS Chip brings out both PGM/RTS and DTS along with RX and TX. This makes it ideal for both Programming and as a USB Serial Bridge. The chip comes loaded with firmware that uses free programming software supplied by Northern Software.
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The individual pic16f1454s are only $5.00 qty 1 and go down to $2.26 in qty 100+. The price you might be seeing is for actual programmers that are a complete board with all the parts. There are several version listed on their site. I purchased a couple of each of the chips to throw on a breadboard with some of the pics I am using regularly, like 12f1840, 16f1825-29 and 16f18326, just for ease of programming and the usb to serial capabilities built in. The big dream would be a development board using these so that no pickit is ever needed. Like a picduino or ardupic or something like that.
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I built 2 parallel port programer boards years ago. Both had win 98 software I didn't understand ie what the code was doing to the boards transistors and the 12V programming voltage. The software only supported a small number of pics.
This where I show my ignorance. If the program has the pic type header then why does the programmer not program that pic? The hardware, without the usb to ttl, is simple. (?). Is it about the programming software that says what pics it can flash a hex file? Everyone else seems to understand all this.
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It is not as simple as you seem to think. More than a "pic type header" is needed.
Different PIC Chips use different Configuration Registers that can reside at different memory locations. Some chips have 2 Config registers, Some have 10, This needs to be accounted for.
PIC chips use different ICSP programming Specs depending upon "Family" . Timings can be critical. This needs to be accounted for.
PIC Chips can use different voltages for HV programming. This needs to be accounted for lest you acidentally fry something.
Try writing bootloader sometime ..... get my drift ?
Last edit: William Roth 2017-12-02
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Ta William. I said it was over my head before they put pics in programmers.
The joy of flashing my first gcb program to a uno and the led flashed was like "I didn't expect that to work"
I'll look up "how to create a pic bootloader" but it won't mean much to me. Wish I could help.
It's not a bootloader though, it's just flashing hex to chip. Why is that difficult? brief like cos it is.
Anyway, I'm having fun with what I got. Nice job guys. Well dumbed down for non techies (I got a soldering iron) so far.
Please don't sploil it by making it look complicated.
I recomended gcb to picaxe users and got- it looks too complicated. no. picaxe is complicated!
attatched, nostalgia board picture.. when it was not fun.
Anyway, just got my bundle from Northern Software, once I get a bit of sleep, I will post my resutls with programming a pic with GCB and NS. Very exciting stuff, may have to try and give a bit of video, but Evan's vids have intimidated me a bit. Not sure I can come across as well....
Edit, I can't seem to find the flashpic batch file command for NS.... Where did I see that?
Last edit: Moto Geek 2017-12-03
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The MPLAB Xpress board is a very powerful and versatile platform and at the current price of $12 is also great value for money.
In addition to a powerful PIC16F18855 processor the board also has a PIC18LF25K50 Device acting as a Programmer for the 16F18855, eliminating the need for a separate PICKit 3 programmer.
The PIC18LF25K50 Device is also programmed as a USB/Serial Bridge which is capable of running independently of the 16F18855 device.
So what does this mean?
It means that if you have an Xpress Evaluation Board you have the equivalent of a 15 to 20 Dollar FTDI device laying on your desk for free.
The USB bridge works independently of the 16f18855 but it does share the RC0/RC1 pins, so to avoid any possible conflict I created "The Worlds Smallest PIC Program"
RC0 (red in the image) will be the Rx for your PC and Tx for the target device
RC1 (Yellow in the Image) will be Tx from the PC and Rx to your target.
Gnd is next to the RC0 pin.
Remember this is a 3V3 device so use a level converter, or at least resistors in series, if connecting to a 5V target.
As a simple test of the system, place a jumper from RC0 to RC1, open the terminal, select the com port your XPress Board created and send "Hello World!".
So next time you are struggling to find that elusive FTDI board, just grab your ever versatile Xpress board instead.
Cheers!
Chris
Last edit: Chris Roper 2017-11-17
Interesting. check this https://www.youtube.com/watch?v=qqSLwK1DP8Q
Chris, I was thinking about using rb.7,rb.6 and mclr wired to another board with a "new" similar pic and use icsp instead of pickit3 and the perceived bother. daft idea? Worth trying?
Won't work Stan,
The PGC and PGD pins have not been brought out to headers so you can't use
it as a programmer.
I tried., even if you cut the boards apart you can't access them, only the
USB/Serial is available.
No... cut the board. I want to know what happens.
:-)
If it would have worked someone would have done it probably.
How many layers is the board? Not cutting :)
This one may be able to do it.
Part Number: DM164141 - MPLABXpress PIC16F18345 Evaluation Board
The programming pins are RA0 and RA1, Mclr is RA3.
All of which are brought out to the edge.
As the device is not socketed you would probably have to lift it and sacrefice the development board aspect.
On the up side you would be getting a Programmer, dual supply and USB/USART Bridge for $12.
Could be worth while, but is untested.
Last edit: Chris Roper 2017-11-28
Or, you can buy one of these for $5 and have a programmer and serial bridge with just a couple of extra parts.
http://www.northernsoftware.com/buy/buy.cgi?cr=1&rq=paj&sc=USD
moto:- cookies required. I'm paranormal with internet.
mike:-the gcb team would have thought of using that...probably.
The NSDS Chip brings out both PGM/RTS and DTS along with RX and TX. This makes it ideal for both Programming and as a USB Serial Bridge. The chip comes loaded with firmware that uses free programming software supplied by Northern Software.
Its also quite a bit faster than the pickit 3 and supports a whole bunch of 8 bit pics and a lot of other families also.
Motogeek. $5 ? site says 35 to 43 euros
The individual pic16f1454s are only $5.00 qty 1 and go down to $2.26 in qty 100+. The price you might be seeing is for actual programmers that are a complete board with all the parts. There are several version listed on their site. I purchased a couple of each of the chips to throw on a breadboard with some of the pics I am using regularly, like 12f1840, 16f1825-29 and 16f18326, just for ease of programming and the usb to serial capabilities built in. The big dream would be a development board using these so that no pickit is ever needed. Like a picduino or ardupic or something like that.
I built 2 parallel port programer boards years ago. Both had win 98 software I didn't understand ie what the code was doing to the boards transistors and the 12V programming voltage. The software only supported a small number of pics.
This where I show my ignorance. If the program has the pic type header then why does the programmer not program that pic? The hardware, without the usb to ttl, is simple. (?). Is it about the programming software that says what pics it can flash a hex file? Everyone else seems to understand all this.
Stan,
It is not as simple as you seem to think. More than a "pic type header" is needed.
Different PIC Chips use different Configuration Registers that can reside at different memory locations. Some chips have 2 Config registers, Some have 10, This needs to be accounted for.
PIC chips use different ICSP programming Specs depending upon "Family" . Timings can be critical. This needs to be accounted for.
PIC Chips can use different voltages for HV programming. This needs to be accounted for lest you acidentally fry something.
Try writing bootloader sometime ..... get my drift ?
Last edit: William Roth 2017-12-02
Ta William. I said it was over my head before they put pics in programmers.
The joy of flashing my first gcb program to a uno and the led flashed was like "I didn't expect that to work"
I'll look up "how to create a pic bootloader" but it won't mean much to me. Wish I could help.
It's not a bootloader though, it's just flashing hex to chip. Why is that difficult? brief like cos it is.
Anyway, I'm having fun with what I got. Nice job guys. Well dumbed down for non techies (I got a soldering iron) so far.
Please don't sploil it by making it look complicated.
I recomended gcb to picaxe users and got- it looks too complicated. no. picaxe is complicated!
attatched, nostalgia board picture.. when it was not fun.
Last edit: stan cartwright 2017-12-02
Anyway, just got my bundle from Northern Software, once I get a bit of sleep, I will post my resutls with programming a pic with GCB and NS. Very exciting stuff, may have to try and give a bit of video, but Evan's vids have intimidated me a bit. Not sure I can come across as well....
Edit, I can't seem to find the flashpic batch file command for NS.... Where did I see that?
Last edit: Moto Geek 2017-12-03