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PE Question:
While using Metrowerks CW6.1.1 processor expert tool, to generate code for the 56F8357EVM, I am having a problem with the automatically generated code. When I use the stationary to create a project, the tool builds a file "pe_types.h". Within this file there is a definition of "SaveStatusReg" which saves the status register, masks interrupts, and inserts 2 nop's. This definition is later used in the same file in another definition of "EnterCritical" which is used by the SCI bean, and others I believe. The problem comes when running the SCI0 peripheral, in that it appears that there needs to be 3 nop's following the setting of the interrupt masks to prevent the serial interrupt code from being interrupted after the first instruction of the "critical region of execution." Of course I cannot legitimately "edit" these files sci bean or pe_types.h without losing the edits every time processor expert runs. Has anyone else seen this "bug" or found a switch or file to modify to insert 3 nops following the masking of interrupts? Jerry. ________________________________________________________________________ This email has been scanned for all viruses by the MessageLabs SkyScan service. For more information visit http://www.messagelabs.com ________________________________________________________________________ |
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PE Question:
Started by ●June 28, 2004
Reply by ●June 30, 20042004-06-30
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Couple of notes here: First, when disabling interrupts on 56F83xx devices, you may need as many as 6 NOPs after the instruction that sets SR to disable interrupts, due to pipeline. Second, it is very easy to modify PE generated code and to preserve your changes. You can: 1. Generate initial code and suspend PE completely. This option will remove PE functionality from your project, but it will keep all generated code, so you can modify any file without PE overwriting it. To do that, go to "Processor Expert" menu and select "Suspend Processor Expert". 2. Generate initial code and "freeze" PE code generation. This option will keep PE functionality in your project with exception of code generation. To do that, go to "Processor Expert" menu and select "Freeze generated code". 3. Suspend code generation for selected beans only. This option will "freeze" code generation for a user specified beans, while generating code for the rest of the project. To do that, go to "Edit/??????_setting" menu (located just under Edit/Preferences menu). In Settings window go to "Processor Expert/Project options" panel (this is very last on the list). Select "Preserve User Changes" check box. Now in your project, right mouse click on SCI bean and make sure that "Code Generation/ Preserve User Changes" option is selected. 4. Enable "track changes" option in PE, which will inform you which files have been changed during code generation and if you want to keep old or new file. It also provides visual diff on old and new version of changed file. To do that, go to "Edit/??????_setting" menu (located just under Edit/Preferences menu). In Settings window go to "Processor Expert/Project options" panel (this is very last on the list). Select "Track/Review Changes" check box. In your case, I suggest to use options 1, 2, or 4 above. Option 3 will not work for you if you modify pe_types.h file, because it is not part of the bean. However, you can modify SCI bean code itself, and place NOPs after call to EnterCritical() function. If you do that, you can use option 3 above and preserve your bean code changes. There will be update or patch for the PE in near future to correct this NOP issue. Sincerely, Leonard --- In , "Johnson, Jerry" <jljohnson@g...> wrote: > While using Metrowerks CW6.1.1 processor expert tool, to generate code for > the 56F8357EVM, I am having a problem with the automatically generated code. > When I use the stationary to create a project, the tool builds a file > "pe_types.h". Within this file there is a definition of "SaveStatusReg" > which saves the status register, masks interrupts, and inserts 2 nop's. > This definition is later used in the same file in another definition of > "EnterCritical" which is used by the SCI bean, and others I believe. > > The problem comes when running the SCI0 peripheral, in that it appears that > there needs to be 3 nop's following the setting of the interrupt masks to > prevent the serial interrupt code from being interrupted after the first > instruction of the "critical region of execution." > > Of course I cannot legitimately "edit" these files sci bean or pe_types.h > without losing the edits every time processor expert runs. > > Has anyone else seen this "bug" or found a switch or file to modify to > insert 3 nops following the masking of interrupts? > > Jerry. > _____________________________________________________________________ ___ > This email has been scanned for all viruses by the MessageLabs SkyScan > service. For more information visit http://www.messagelabs.com > _____________________________________________________________________ ___ |
