mark.sea...@gmail.com wrote:
I'm trying to make a script environment with datatypes (or classes)
for accessing hardware registers. At the top level, I would like the
ability to bitwise ops if bit slice brackets are used, but if no
brackets are used, I would like it to write/read the whole value.
For example, if I have something like:
shadow_register = MyRegClass(0xAA)
shadow_register
170
shadow_register[7:4] = 3 # <== changes value to 0x3A
shadow_register
58
shadow_register = 0x89
shadow_register
137
shadow_register[4:1]
4
I have the bitslice part working. But of course as expected, if I
type
shadow_register
<__main__.boo object at 0x00A130D0>
I wanted to avoid having something like shadow_register.value just
because it's clumsier. I read about the __new__() class for
overriding the classtype, like:
print 'foo'
class foo(object):
def __new__(*args): return 0
but if I stick in a __init__(self, val): method, then it chokes saying
val is a global name that's not defined.
Now I know that I have to live with the fact that I can't have
shadow_register = 0x89
Because it will get reassigned from my class value to a newly
intialized memory location (int object). But can I have it read the
value without the .value extension? Is this even possible? Maybe
there's a way to override the = operator? (Go easy on me - I'm a
hardware guy).
Interesting what you're doing. I've struggled with the same issues,
simulating a pic,
never really solved them.
Maybe this is what you're looking for:
class MyRegClass ( object ) :
def __init__ ( self, value ) :
self.Value = value
def __repr__ ( self ) :
line = hex ( self.Value )
line = line [:2] + line [2:].upper()
return line
btw, I'm a hardware guy too, and therefor I've never understood why the
hex function returns lowercase ;-)
cheers,
Stef
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