Microcontroller Project

Discussion in 'Embedded Systems and Microcontrollers' started by mwalden824, May 16, 2011.

  1. mwalden824

    Thread Starter Member

    Mar 6, 2011
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    2
    Hello. I haven't posted here in awhile. The last time I did I was just starting out in electronics, just reading on my own, like from this site and some books. I have gotten a little more educated since then, and I am now in school at a University for Electrical Engineering. I just finished a class on Microprocessor Systems and Interfacing and the book we used specifically demonstrated the use of the Motorola 68hc11. I have since come to realize that this isn't a very popular choice, as things for this unit are hard to find. I am taking the Lab to this class this fall and I have found the evaluation board that we will be using. I plan on buying this board and doing some things with it over the summer. I am really excited about this type of work, because it is the most interesting to me so far. It is the only class, so far, that we have discussed the design of useful products that I think I might be able to carry out, at least the small things, like maybe a clock.

    Anyway enough about me. I was hoping to get some guidance and some answers to a few questions that I have about this chip and microcontrollers in general.

    First, do these evaluation boards typically come with a socket so the chip can be removed for implantation in a better suited hardware setup? Like if I designed a clock, could I just take the chip out once I got it working on the evaluation board, and solder it into my own board to put in a case? I couldn't tell from the pictures of any of them and it doesn't seem to say? My interpretation of the purpose of these boards are that they are just for learning, so I assume that maybe the chips can't be easily removed without ripping it off and risk damaging the chip?

    If this can't be done easily, how exactly can I get my programs onto the chip? I know that this differs with different chips, and I see most people here are more familiar with the PIC and others, but I am confused about this. Couldn't I just buy an EEPROM programmer, and put an EEPROM chip in this and program my programs to that, then wire the 68hc11 in expanded mode to this chip? I mean I know this will work, but the reset vector on the memory inside the 68hc11 has to be changed to where the program resides in the external EEPROM correct? So no matter what, I will have to somehow get my program or atleast the new vector pointing to it on the 68hc11?

    I have read some things on the website of the professor that will be instructing the lab this fall, and he mentions buffalo, which is some sort of serial communication setup which I think we will use to get the programs on the evaluation board, but will this work just for a regular 68hc11 chip not on a board, and if so what hardware do I need to get it to work? I assume some type of programmer, and cable? Can I just make it? Are there schematics? I can't seem to find anything useful like there is for the PIC.

    If anyone has a website or something that can describe to me loading a program onto this chip I would greatly appreciate it. I am really excited about making something from what I learned from this class and I don't want to wait until fall to do it.

    I also thought that maybe I could just buy some PICs and maybe a PIC kit because I have found a ton of stuff on this chip, including everything I need to get started. I was just worried about how long would it take me to pick up on this chip after learning the 68hc11 and if it would interfere with me learning the 68hc11 since my lab will be on it and not the PIC?

    Thanks for any help and sorry for the long post of newbie questions.
    Michael Walden
     
  2. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    Well I don't have many good things to say about EEPROMS, to me they are a bad memory of a time when things just worked well enough to get by, even though you can electronically erase them now. Days past we had to expose them to UV light for a while to get them blank again.

    I do like the Microchip parts and use them frequently. They have excellent inexpensive dev kits. I love my PickitII (I hear the Pickit3 is not as good but still works well) and my ICD 3 is also excellent. You can get a Pickit with a small dev board that will get you doing some nice things right off.

    Their dev boards do have a small prototyping area, so if you wished you can just drop that board into a project. I've done that in a prototype once, but I prefer to just start fresh on an empty breadboard and go from there.

    Microchip gives free versions of a C compiler if you stick to the 18 or higher series of parts. They are slightly crippled but quite useful, and you get full rights with them. Otherwise they give away a complete assembler environment (MPLAB) that can also do simulation and in circuit debugging using either a Pickit (most parts) or the ICD (more parts including the 32 bit ones).

    Sorry I don't have any expierence with the 68hc11.
     
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  3. hgmjr

    Moderator

    Jan 28, 2005
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    If you want to have access to free uncrippled software development package then you will want to consider also the ATMEL AVR. One of the things that makes the AVR attractive to me is that all of the members of the AVR ATMEGA and ATTINY AVR 8-bit microcontroller family are built around the same CPU core. That means that once you have become familiar with one of the microcontrollers you will be familiar with all of the members of the AVR 8-bit micrcontrollers. This means that as you work your way up from the smallest device all the way up to the most complex member of the AVR 8-bit microcontroller family you will be able to use the same programming tools and the same free uncrippled software development envirionment.

    Since you are just beginning to learn the 68HC11 microcontroller then you are most likely using assembly language which means you probably are not yet familiar with C-Langauge. The AVR family also has a free uncrippled C-language compiler that works with AVRSTUDIO4 to provide you with C programming experience.

    No matter which way you go, you have a tremedously enjoyable adventure ahead of you as you explore the current array of microcontrollers available to you. There is no way but up from here.

    hgmjr
     
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  4. mwalden824

    Thread Starter Member

    Mar 6, 2011
    51
    2
    Thank you both for your help. I guess maybe flash would be a better memory option. Didn't think about that because my book doesn't mention it. It's kinda old. The 68hc11 must not be used much anymore, and I am wondering why my school still teaches it instead of one of the newer chips? Probably because it maybe easier to learn for students, I guess.

    I have been looking at both the pic and the avr also now since hgmjr mentioned it. From what I've been reading they are both good microcontrollers, but the avr may be slightly more easier to code for. I've decided against getting the 68hc11 board. I will just wait until Fall to learn this chip in school, this way I will get some experience with 2 chips. I am just a little worried about getting confused when its time to learn the 68hc11, but I will just quit the AVR or PIC until the semester is over with. As for right now I'm probably going to get the EasyAvr6, or the EasyPIC development board, but I am leaning towards the EasyAVR6.

    I Have a couple of quick questions. Are these good boards for a beginner? I do have some experience with C++ programming not C though, but the languages are similar it seems. I Figured I could order the EasyAVR6 board...
    http://www.mikroe.com/eng/products/view/321/easyavr6-development-system/
    and this book...
    http://www.amazon.com/Embedded-C-Pr...=sr_1_1?ie=UTF8&s=books&qid=1263229520&sr=1-1

    This should get me started huh? Also it looks like this board has sockets so the chips can be removed after programming, so I could use it as a programmer correct? Like maybe develop a project on the board and then latter remove the chip to solder in a smaller custom board and casing, correct? I mean I'm sure you can I am just making sure I am understanding this correctly and not overlooking anything before I spend 140 dollars. This looks like an awesome board.

    Thanks again,
    Michael Walden
     
  5. hgmjr

    Moderator

    Jan 28, 2005
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    I am not familiar with this particular board but the EASYAVR6 appears to have everything you could ever want to have at your finger tips for the purpose of learning micrcontrollers.

    hgmjr
     
  6. t06afre

    AAC Fanatic!

    May 11, 2009
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    Does it support in circuit programing. That is very important
     
  7. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    It can do its own programming: "On-board USB 2.0 programmer AVRprog2 doesn't use bootloader or any similar software for programming."

    I don't use AVR's (I use PICs) but I do have a development board from MikroElektronika but I do have their PIC32MX4 MultiMedia Board and find it an excellent platform.
     
  8. hgmjr

    Moderator

    Jan 28, 2005
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    As erniem has indicated, the EasyAVR6 is "in-system programmable". You can use the builtin programmer via the USB port or it also supports the ISP6PIN connection in the event you desire to program it using the AVRMKII programmer.

    Here is a link to the user's manual on-line.

    hgmjr
     
  9. mwalden824

    Thread Starter Member

    Mar 6, 2011
    51
    2
    Cool. Thanks everybody. I am going to order the board and the book. I can't wait to get started. I feel like a little kid at Christmas time, lol.

    Later,
    Michael Walden
     
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