Strange const behavior

[LGR]

I'm working on an ST7565 project, that I intend to put on Libstock when I'm done. In order to keep it readable, I want to be able to declare a constant array of byte thusly:

Code: Select all

const  // Opcodes

V0Ratio             : byte = 0x20; // Add 0-7 for different values
EVRegSet            : byte = 0x00; // Add 0-63 for different contrasts
BoosterRatioReg2X4X : byte = 0x00; // Use in conjunction with BoosterRatioMode
BoosterRatioReg5X   : byte = 0x01; // Use in conjunction with BoosterRatioMode
BoosterRatioReg6X   : byte = 0x03; // Use in conjunction with BoosterRatioMode
ColumnAdressSet     : byte = 0x10; // To create...
BoffVRoffVFoff      : byte = 0x20; // Power controller settings
BoffVRoffVFon       : byte = 0x21;
BoffVRonVFoff       : byte = 0x22;
BoffVRonVFon        : byte = 0x23;
BonVRoffVFoff       : byte = 0x24;
BonVRoffVFon        : byte = 0x25;
BonVRonVFoff        : byte = 0x26;
BonVRonVFon         : byte = 0x27;
DisplayStartLineSet : byte = 0x40; // Arithmetically add line number to this
EVModeSet           : byte = 0x81;
ADCSelectNormal     : byte = 0xA0;
ADCSelectReverse    : byte = 0xA1;
LCDBiasSet1         : byte = 0xA2; // See ST7565R manual
LCDBiasSet2         : byte = 0xA3;
AllPixOn            : byte = 0xA4;
AllPixOff           : byte = 0xA5;
DisplayNormal       : byte = 0xA6;
DisplayReverse      : byte = 0xA7;    
CMDDispOff          : byte = 0xAE;
CMDDispOn           : byte = 0xAF;
PageAdressSet       : byte = 0xB0; // Arithmetically add page number to this
CommonOutModeSel1   : byte = 0xC0;
CommonOutModeSel2   : byte = 0xC8;
ReadModifyWrite     : byte = 0xE0; // See RMW command, and how it works with
ENDlcd              : byte = 0xEE; // END command
Resetlcd            : byte = 0xE2;
NOP                 : byte = 0xE3;
BoosterRatioMode    : byte = 0xF8;

const displaytech   : array[20] of byte =
(DisplayStartLineSet,
ADCSelectNormal,
CommonOutModeSel2,
DisplayNormal,
LCDBiasSet1, 0x2F,
BoosterRatioMode, 0x00,
BonVRonVFon,
EVModeSet, 0x04,
0xAC,
EVRegSet,
CMDDispOn, 
NOP, NOP, NOP, NOP, NOP, NOP);

The last declaration (displaytech) doesn't compile. The compiler says that there are too many arguments. I count 20. Am I missing something?

[filip]

Hi,

The NOP is a built-in identifier, associated to asm nop, and therefore it shouldn't be used as an identifier name.
The compiler also shouldn't allow the constant declaration with NOP being constant identifier, which we will fix.

Regards,
Filip.

[LGR]

That fixed it. Is there an easy way to get a list of all reserved identifiers for a given chip?

[janni]

Those are declared in definition *.mpas file for a given processor.
There's also a list of reserved keywords in Help. NOP is not present there as it's a routine - unfortunately it's also omitted in built-in routines list.

When in doubt, one may always invoke Code Assistant to check whether an identifier is not already used (place cursor on doubted identifier and press Ctrl+Space).

[LGR]

I noticed that certain built-in routines that are simple ASM commands (such as RESET) aren't documented. All of these should be listed in the documentation under built-in commands.

[janni]

Actually, RESET and Clrwdt are listed in built-in routines, only NOP somehow got lost.

[LGR]

And of course, NOP is also an instruction for the ST7565. So we have yet another potential type of conflict. This is why I decided that ALL variables in this library will start with "ST". Now watch this conflict with some device made by ST (which the ST7565 isn't).

I already had a conflict with "WR" as a name for a pin.

[filip]

Hi,

Thank you janni for this suggestion, we will add it to the Help file.

Regards,
Filip.