Hello,
I have a problem. I am currently unable to buy over the internet so I am stuck to stock atmega-s.
I have a windows vista pc with parallel port that I csn use only once per werk and xp laptop which is mine(but lacks parallel port). Anyway, I am going to vacation for a longer time and dont want to waste my time since I have interesting project in mind and i would like to experiment while on vacation.So I am stuck to buying either stock atmega 328 or atmega8.
My question is, is it possible to bootload atmega 328 with parallel programmer? Has anyone done it?
In essence, I would have to succeed in uploading bootloader over parallel port so that I can use my laptop with microcontroller.
I have done that, and it worked.
The one I made is called "SP12". I can find different versions with different resistors and I don't know which one I made.
But this one might work : http://www.gc-forever.com/wiki/index.php?title=XenoGC_Clone
Search for SP12 on that page.
MCUbeginnerx47:
Hello,
I have a problem. I am currently unable to buy over the internet so I am stuck to stock atmega-s.
I have a windows vista pc with parallel port that I csn use only once per werk and xp laptop which is mine(but lacks parallel port). Anyway, I am going to vacation for a longer time and dont want to waste my time since I have interesting project in mind and i would like to experiment while on vacation.So I am stuck to buying either stock atmega 328 or atmega8.
My question is, is it possible to bootload atmega 328 with parallel programmer? Has anyone done it?
In essence, I would have to succeed in uploading bootloader over parallel port so that I can use my laptop with microcontroller.
Homemade paralel programmer
Homemade serial programmer (works only on real serial port, not usb-serial adapters) http://m.instructables.com/id/AVR-ISP-programmer/?ALLSTEPS
How are you going to program afterwards the atmega with laptop? Some ftdi device?
Thanks.
I was thinking about building programmer that is depicted on arduino website, but it only mentions atmega8, so thats why i was confused.
After I burn bootloader, I am going to programm it over max 232 - ttl converter.
Just to inform you guys. I have found UNO preloaded atmega 328 on the website of my local store 
Not sure how many are left in stock. Gotta hurry!
MCUbeginnerx47:
Just to inform you guys. I have found UNO preloaded atmega 328 on the website of my local store
Not sure how many are left in stock. Gotta hurry!
Lol. Eventually you'll need an external programmer to change fuses or rewrite bootloader at different clockspeed. Maybe you can use arduino as isp programmer.
I dont have Arduino board. Bare bones atmega suits my project much better.
Why would I need to set fuses? It says its set for 16 mhz crystal? Is it something that happens over time that will cause me to need to rewrite bootloader?
One more question. Do you think that atmega 328 (Arduino Uno) has the capability to run 1 stepper motor (in short intervals 2) AND listen to serial string commands? Is it powerful enough to handle that?
MCUbeginnerx47:
One more question. Do you think that atmega 328 (Arduino Uno) has the capability to run 1 stepper motor (in short intervals 2) AND listen to serial string commands? Is it powerful enough to handle that?
A dozen stepper motors, no doubt. It's all a matter of knowing how to write code - not entirely implicit in the basic "tutorials" however.
But don't expect to drive them without the corresponding driver chips.
Regarding your previous queries, it seems you are constrained for time, but given a laptop with a USB port, what you really need is an "ISP programmer".
MCUbeginnerx47:
Why would I need to set fuses? It says its set for 16 MHz crystal? Is it something that happens over time that will cause me to need to rewrite bootloader?
Of course not. If it is set for a 16 MHz crystal, you are doing fine, but of course you need the 16 MHz crystal and the padding capacitors and a number of 0.1µF bypass capacitors and the 10k pull-up on the reset line.
MCUbeginnerx47:
I dont have Arduino board. Bare bones atmega suits my project much better.
Why would I need to set fuses? It says its set for 16 mhz crystal? Is it something that happens over time that will cause me to need to rewrite bootloader?
No haha dont worry nothing of that will happen.
If you buy atmega with bootloader inside, fuses are already set and you dont have to worry anymore.
I was trying to say that in future proyects if you want to run atmega at 8 mhz with internal clock (which is less power consuming) you'll need an external programmer to change clock.
Just to clarify. Is this RS 232 converter schematic fine?
I have all the needed parts and just want the confirmation so that i can proceed with the build.
I mean, there is at least a dozen rs 232 converter circuits on the net, some incorporating max 232, some not. It is really confusing.
MCUbeginnerx47:
Just to clarify. Is this RS 232 converter schematic fine?
Not bad, probably will work, particularly at short range. It approximates an RS-232 port. It is safe. MAX232 provides genuine RS-232 interface levels.
So the laptop you have (not recent then) definitely has the DE-9-pin RS-232 port rather than or as well as a USB port?
So I should use max232 then. Any particular circuit that you recommend? I have seen a few, and might go for this one, if i choose max 232: http://www.circuit-projects.com/cimg/ttl-level-rs232-level-converter-by-max232.jpg
Laptop has both 1 genuine rs 232 and 4 usb ports, but i cant buy ftdi adapter since i am currently unable to buy over net and there are no ftdi adapters at any of my local stores.
And yeah, laptop is anything but recent, lol.
MCUbeginnerx47:
So I should use max232 then. Any particular circuit that you recommend? I have seen a few, and might go for this one, if i choose max 232: http://www.circuit-projects.com/cimg/ttl-level-rs232-level-converter-by-max232.jpgLaptop has both 1 genuine rs 232 and 4 usb ports, but i cant buy ftdi adapter since i am currently unable to buy over net and there are no ftdi adapters at any of my local stores.
And yeah, laptop is anything but recent, lol.
The schematic you posted is ok. I would read the max232 datasheet anyway because they have an schematic too. And watch out for the capacitors on the max232. If you use polarized caps be carefull with the orientation. Some max232 chips can hold from 0.1uf to 10uf caps, I've always worked with 4.7uF electrolytic caps, but some guys say that 0.1uF ceramic caps (without polarity) work too.
Other thing to remember, max232 has 2 channels of convertion, so you may use any.
Whats the easiest way to test the circuit without atmega so that i am sure that it will work? (still havent bought bootloaded atnega)
EDIT: OK, I know i am getting really boring, but would i be better off with this o thing?
http://cdn.instructables.com/FZS/3773/HH2VXTDJ/FZS3773HH2VXTDJ.MEDIUM.gif
I have already started rs 232 ttl converter, but i was thinking, this is both programmer and rs232 communication tool.
I will still finish max 232 build, but what do you think about this one? Could it be used as a programmer and communication tool with an avr?
EDIT 2: Just realized how stupid this second question (about programmer) is. Never mind. Overlook that question.