SFR definitions and 'system' keyword

[Jerry Messina]

In the device files SFR's are defined with the 'system' attribute, ie

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public system MAADR5 as byte absolute $0E80

What would be the difference if it was just declared as a regular byte as

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public dim MAADR5 as byte absolute $0E80

Does the compiler treat 'system' as special somehow?

[David Barker]

If memory serves the system keyword isn't used by the compiler any more (port is though). However, I have maintained using system to declare SFR's for all system modules.

[Jerry Messina]

Is there some special meaning attached to EDATA?

If I try

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public system EDATA as byte absolute $0F61

when I go to use it I get 'Error(47): Comma missing'

If I declare it w/out 'system' it works.

[David Barker]

Yes, that is an anomaly. The parser will not name mangle "system" variables (so this contradicts my previous post, system is treated differently!). The code generator is falling over on the non mangled EDATA. What is it you are trying to do?

[Jerry Messina]

The J60 Ethernet chips have a SFR named EDATA @ $0F61 and the device files are getting it wrong.

It seems I already addressed this in the updated SystemConvert app I sent you a link to a few weeks ago. I just forgot to copy over the new device files to this machine.

According to the sysgen source comments, EDATA needs special treatment. I forgot about that.

[David Barker]

Yes, it typically gets called EEDATA I think

[Jerry Messina]

Gotcha. So since it uses EDATA instead of EEDATA, trying to declare 'system EDATA' for the J60 register name was an issue. Seems to work fine just declaring EDATA as 'public dim', so that's no problem.

This wouldn't have been an issue if I could have remembered that I already went down this road a month ago!