|
Two questions: First: Will Codewarrior 3 for HCS12 support full ANSI C++ ? I'm using 1.2, and it didn't support the full standard, even though Metrowerks said it had "Full ANSI C++ draft". After testing the compiler and reading some help files, it appears that one should read it as "Full ANSI C++ that isn't full"... it didn't support exception handling, RTTI, C++ casting etc. I am currently developing HCS12 programs in C, but I might change to C++ in the future. I will probably upgrade to CW3 whether it supports full C++ or not; but still I would like to know if it is supported. A second question: is there anyone out there using C++ on HCS12? Does it work well or do you have to skip/workaround some features in the language because lack of memory etc? I think that the S12 exists in some kind of grey zone between a powerfull MCU that can handle OS & C++ without problems, and a traditional "small" microcontroller. Thanks / Daniel |
|
|
Codewarrior 3 and C++
Started by ●October 30, 2003
Reply by ●October 30, 20032003-10-30
|
I'm using CW V1.2 and C++ with virtual functions. It seems that overhead is not big. And HCS12 family had enough flash and RAM for programming in C++. If you will start with C++, you will never go back to C. So my thinking is that C++ is good for HCS12. But still do not forget ASM. Controlmatik ABW Robert Konc Domzale, Slovenia e-mail: web: www.cm-abw.si tel: +386 1 7213552 fax: +386 1 7219360 -----Original Message----- From: Daniel Lundin [mailto:] Sent: Thursday, October 30, 2003 11:33 AM To: Subject: [68HC12] Codewarrior 3 and C++ Two questions: First: Will Codewarrior 3 for HCS12 support full ANSI C++ ? I'm using 1.2, and it didn't support the full standard, even though Metrowerks said it had "Full ANSI C++ draft". After testing the compiler and reading some help files, it appears that one should read it as "Full ANSI C++ that isn't full"... it didn't support exception handling, RTTI, C++ casting etc. I am currently developing HCS12 programs in C, but I might change to C++ in the future. I will probably upgrade to CW3 whether it supports full C++ or not; but still I would like to know if it is supported. A second question: is there anyone out there using C++ on HCS12? Does it work well or do you have to skip/workaround some features in the language because lack of memory etc? I think that the S12 exists in some kind of grey zone between a powerfull MCU that can handle OS & C++ without problems, and a traditional "small" microcontroller. Thanks / Daniel -------------------- ">http://docs.yahoo.com/info/terms/ |
Reply by ●October 30, 20032003-10-30
|
We are designing a new board around the HC12, but I'm arguing that the
1Kb of RAM is not enough to support programming in C or C++. How much RAM does your system have? How much would you recommend. The design is a replacement for a HC08 design that uses about 256 bytes of RAM. The designer has heard a rule of thumb that a C program would need 4x the RAM of an assembly version (hence the 1kb). Any thought gratefully received. Neil -----Original Message----- From: Robert Konc [mailto:] Sent: 30 October 2003 11:01 To: Subject: RE: [68HC12] Codewarrior 3 and C++ I'm using CW V1.2 and C++ with virtual functions. It seems that overhead is not big. And HCS12 family had enough flash and RAM for programming in C++. If you will start with C++, you will never go back to C. So my thinking is that C++ is good for HCS12. But still do not forget ASM. Controlmatik ABW Robert Konc Domzale, Slovenia e-mail: web: www.cm-abw.si tel: +386 1 7213552 fax: +386 1 7219360 -----Original Message----- From: Daniel Lundin [mailto:] Sent: Thursday, October 30, 2003 11:33 AM To: Subject: [68HC12] Codewarrior 3 and C++ Two questions: First: Will Codewarrior 3 for HCS12 support full ANSI C++ ? I'm using 1.2, and it didn't support the full standard, even though Metrowerks said it had "Full ANSI C++ draft". After testing the compiler and reading some help files, it appears that one should read it as "Full ANSI C++ that isn't full"... it didn't support exception handling, RTTI, C++ casting etc. I am currently developing HCS12 programs in C, but I might change to C++ in the future. I will probably upgrade to CW3 whether it supports full C++ or not; but still I would like to know if it is supported. A second question: is there anyone out there using C++ on HCS12? Does it work well or do you have to skip/workaround some features in the language because lack of memory etc? I think that the S12 exists in some kind of grey zone between a powerfull MCU that can handle OS & C++ without problems, and a traditional "small" microcontroller. Thanks / Daniel -------------------- ">http://docs.yahoo.com/info/terms/ -------------------- ">http://docs.yahoo.com/info/terms/ |
|
|
Reply by ●October 30, 20032003-10-30
|
Old design was made on HC08AZ60A (CW1.2 C for HC08) 59K of ROM 2K of RAM (need more RAM then I start with HCS12DG128) New design (chlorine analyzer with regulator and logging) has HCS12DG128 (working with CW1.2 C++ for HC12 and little with ASM). RTOS(uCOS for C++ like) 12 task GUI for 120x32 LCD 4 sigma delta analog inputs (need floating point aritm. Like sqrt,log) PID regulator (need floating point) SeleCan comm. support Current size (app. 80% of full code) 61K of ROM 2.5K of RAM If I compare size of RAM on ASM and C, it must not be factor 4x. You need deeper stack. Because of temp variables and libraries but that's all. It all depends how you write code. What you need is bigger ROM(Flash). But still not factor 4x. If your C code is design well, overhead of your code must not be bigger than 30% of ASM code (if using CW1.2). In C++ programming is a little bit different. If you using virtual function witch are base for OOP, then the overhead for ROM and RAM is bigger. But family HCS12 has a lot a derivate for complex programming even in C++. Controlmatik ABW Robert Konc Domzale, Slovenia e-mail: web: www.cm-abw.si tel: +386 1 7213552 fax: +386 1 7219360 -----Original Message----- From: Neil Scales [mailto:] Sent: Thursday, October 30, 2003 12:10 PM To: ' Subject: RE: [68HC12] Codewarrior 3 and C++ We are designing a new board around the HC12, but I'm arguing that the 1Kb of RAM is not enough to support programming in C or C++. How much RAM does your system have? How much would you recommend. The design is a replacement for a HC08 design that uses about 256 bytes of RAM. The designer has heard a rule of thumb that a C program would need 4x the RAM of an assembly version (hence the 1kb). Any thought gratefully received. Neil -----Original Message----- From: Robert Konc [mailto:] Sent: 30 October 2003 11:01 To: Subject: RE: [68HC12] Codewarrior 3 and C++ I'm using CW V1.2 and C++ with virtual functions. It seems that overhead is not big. And HCS12 family had enough flash and RAM for programming in C++. If you will start with C++, you will never go back to C. So my thinking is that C++ is good for HCS12. But still do not forget ASM. Controlmatik ABW Robert Konc Domzale, Slovenia e-mail: web: www.cm-abw.si tel: +386 1 7213552 fax: +386 1 7219360 -----Original Message----- From: Daniel Lundin [mailto:] Sent: Thursday, October 30, 2003 11:33 AM To: Subject: [68HC12] Codewarrior 3 and C++ Two questions: First: Will Codewarrior 3 for HCS12 support full ANSI C++ ? I'm using 1.2, and it didn't support the full standard, even though Metrowerks said it had "Full ANSI C++ draft". After testing the compiler and reading some help files, it appears that one should read it as "Full ANSI C++ that isn't full"... it didn't support exception handling, RTTI, C++ casting etc. I am currently developing HCS12 programs in C, but I might change to C++ in the future. I will probably upgrade to CW3 whether it supports full C++ or not; but still I would like to know if it is supported. A second question: is there anyone out there using C++ on HCS12? Does it work well or do you have to skip/workaround some features in the language because lack of memory etc? I think that the S12 exists in some kind of grey zone between a powerfull MCU that can handle OS & C++ without problems, and a traditional "small" microcontroller. Thanks / Daniel -------------------- ">http://docs.yahoo.com/info/terms/ -------------------- ">http://docs.yahoo.com/info/terms/ -------------------- ">http://docs.yahoo.com/info/terms/ |
Reply by ●October 30, 20032003-10-30
|
Neil Scales wrote: > We are designing a new board around the HC12, but I'm arguing that the 1Kb ^^^^^^^^ _the_ HC12? BTW: there are derivatives with much more than 1K RAM. > of RAM is not enough to support programming in C or C++. How much RAM does > your system have? How much would you recommend. > > The design is a replacement for a HC08 design that uses about 256 bytes of > RAM. The designer has heard a rule of thumb that a C program would need 4x > the RAM of an assembly version (hence the 1kb). A C program doesn't necessarily need noticeable more RAM than assembly. It shouldn't do anything you don't request, and if you don't use library functions or deep nesting, you will not see any difference. I suggest you invest some time to become familiar with C, get a trial version of a good compiler and look at the output. Check at least Cosmic and/or CodeWorrier before you decide on another compiler (ICC, GCC). Oliver -- Oliver Betz, Muenchen |
Reply by ●October 30, 20032003-10-30
|
At 08:09 a.m. 30/10/03, you wrote: >We are designing a new board around the HC12, but I'm arguing that the 1Kb >of RAM is not enough to support programming in C or C++. How much RAM does >your system have? How much would you recommend. I recommend that you procure enough ram to produce faster code. But you can use C on microcontrollers with very low resources. Several years ago I wrote a C program runing on a 68705C8. >The design is a replacement for a HC08 design that uses about 256 bytes of >RAM. The designer has heard a rule of thumb that a C program would need 4x >the RAM of an assembly version (hence the 1kb). It's not true. If you can write C programs on HC08 with 256 bytes of RAM. Of course you meed more imagination. Kindly Bob |
Reply by ●October 30, 20032003-10-30
|
I've successfully used C on smaller micros (Cypress PSoC, for instance)
with only 256 bytes of RAM. It's mostly a matter of discipline in writing function calls with minimal parameters and being careful about how many local variables you use and deeply you nest calls. While I agree that more is better, RAM-wise, 1k is enough for reasonably careful C coding and the 'hc12 variants with more than 1k will give you plenty of space to work in. /s/jar () http://www.mtritter.org EMAIL DISCLAIMER Please Note: The information contained in this message may be privileged and confidential, protected from disclosure, and/or intended only for the use of the individual or entity named above. If the reader of this message is not the intended recipient, or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any disclosure, distribution, copying or other dissemination of this communication is strictly prohibited. If you received this communication in error, please immediately reply to the sender, delete the message and destroy all copies of it. Thank You |
Reply by ●October 31, 20032003-10-31
|
Neil Scales <neils@testomet To: "'" <> ric.co.uk> cc: Subject: RE: [68HC12] Codewarrior 3 and C++ 10/30/2003 03:09 AM Please respond to 68HC12 There have been several good replies to this email, and I'll add my two cents worth... I was working with a recent 68hc12 port of GCC and had rewritten several of the common platform-dependent functions (serial I/O, etc.). I was targeting a 'b32 and had a little C program ready to go, but the linked executable exceeded 32K flash, when I was expecting less than 4K. Digging through the map file showed that one library routine (forget which) was dragging in all the double operators, which I clearly did not need. I ended up recoding that library routine and got the executable size I was expecting. I remember being surprised by the offending routine; it wasn't one of the obvious ones, like printf(). Something to do with classification or formatting... Moral is that if your first attempts on your project result in excessive RAM/ROM requirements, you might have to provide stripped-down versions of some (possibly obscure) library routines. I would argue against replacing the functions in the GCC object libraries; instead, name your versions something similar but different and link them in. Karl We are designing a new board around the HC12, but I'm arguing that the 1Kb of RAM is not enough to support programming in C or C++. How much RAM does your system have? How much would you recommend. The design is a replacement for a HC08 design that uses about 256 bytes of RAM. The designer has heard a rule of thumb that a C program would need 4x the RAM of an assembly version (hence the 1kb). Any thought gratefully received. Neil ________________________________________________________________________ ________________________________________________________________________ This email has been scanned for all viruses by the MessageLabs Email Security System. For more information on a proactive email security service working around the clock, around the globe, visit http://www.messagelabs.com ________________________________________________________________________ |
