set x "2 * 6"
set foo([expr $x]) "twelve"
-
+
**************************************************
***************************************************
=== TCL TOUR ===
===============
First, there is a "for" loop - at level 0
-{level 0 means: out side of a proc/function}
+{level 0 means: outside of a procedure/function}
This means it is evaluated when the file is parsed.
In TCL, "FOR" is a funny thing, it is not what you think it is.
Syntactically - FOR is a just a command, it is not language
-construct like for(;;) in C...
+construct like for(;;) in C...
The "for" command takes 4 parameters.
(1) The "initial command" to execute.
5) Goto Step 2.
As show, each of these items are in {curly-braces}. This means they
-are passed as they are - KEY-POINT: un evaluated to the FOR
+are passed as they are - KEY-POINT: unevaluated to the FOR
command. Think of it like escaping the backticks in Bash so that the
-"under-lying" command can evaluate the contents. In this case, the FOR
+"underlying" command can evaluate the contents. In this case, the FOR
COMMAND.
== END: SIDEBAR: About The FOR command ==
you think. But here's how:
First - the line is parsed - for {braces}. In this case, there are
-none. The, the parser looks for [brackets] and finds them. The,
+none. Then, the parser looks for [brackets] and finds them. The
parser then evaluates the contents of the [brackets], and replaces
-them. It is alot this bash statement.
+them. It is similar to this bash statement.
EXPORT vn=`date`
LINE 2 & 3
- set $vn [expr (1024 * $x)]
+ set $vn [expr {1024 * $x}]
global $vn
In line 1, we dynamically created a variable name. Here, we are
assigning it a value. Lastly Line 3 we force the variable to be
-global, not "local" the the "for command body"
+global, not "local" within the "for command body"
===============
The PROCS
Again, this is at "level 0" so it is a global function. (Yes, TCL
supports local functions, you put them inside of a function}
-You'll see in some cases, I nest [brackets] alot and in others I'm
+You'll see in some cases, I nest [brackets] a lot and in others I'm
lazy or wanted it to be more clear... it is a matter of choice.
===============
(2) NAME( array )
And the array must have some specific names:
( <idx>, THING )
- Where: THING is one of:
+ Where: THING is one of:
CHIPSELECT
BASE
LEN
RWX - the access ability.
WIDTH - the accessible width.
- ie: Some regions of memory are not 'word'
+ i.e.: Some regions of memory are not 'word'
accessible.
The function "address_info" - given an address should
MAJOR FUNCTION:
==
-proc memread32 { ADDR }
-proc memread16 { ADDR }
-proc memread8 { ADDR }
+proc memread32 { ADDR }
+proc memread16 { ADDR }
+proc memread8 { ADDR }
All read memory - and return the contents.
[ FIXME: 7/5/2008 - I need to create "memwrite" functions]
-
+
**************************************************
***************************************************
=== TCL TOUR ===
FOO_linux = "Penguins rule"
FOO_winXP = "Broken Glass"
FOO_mac = "I like cat names"
-
+
# Pick one
BUILD = linux
#BUILD = winXP
#BUILD = mac
FOO = ${FOO_${BUILD}}
-
+
The "double [set] square bracket" thing is the TCL way, nothing more.
----
error [format string...]
}
-The "IF" command expects either 2 params, or 4 params.
+The "IF" command expects either 2 or 4 parameters.
=== Sidebar: About "commands" ===
-
+
Take a look at the internals of "jim.c"
Look for the function: Jim_IfCoreCommand()
And all those other "CoreCommands"
You'll notice - they all have "argc" and "argv"
Yea, the entire thing is done that way.
-
+
IF is a command. SO is "FOR" and "WHILE" and "DO" and the
others. That is why I keep using the phase it is a "command"
-
+
=== END: Sidebar: About "commands" ===
Parameter 1 to the IF command is expected to be an expression.
You give CATCH 1 or 2 parameters.
The first 1st parameter is the "code to execute"
The 2nd (optional) is where to put the error message.
-
+
CATCH returns 0 on success, 1 for failure.
- The "![catch command]" is self explaintory.
+ The "![catch command]" is self explanatory.
The 3rd parameter to IF must be exactly "else" or "elseif" [I lied
be joined by exactly the words "else" or "elseif".
The 4th parameter contains:
-
+
"error [format STRING....]"
This lets me modify the previous lower level error by tacking more
And - if it does - I call the function.
-In "C" it is alot like using: 'sprintf()' to construct a function name
+In "C" it is a lot like using: 'sprintf()' to construct a function name
string, then using "dlopen()" and "dlsym()" to look it up - and get a
function pointer - and calling the function pointer.
In this case - I execute a dynamic command. You can do some cool
-tricks with interpretors.
+tricks with interpretors.
----------
The "CHIP" file has defined some variables in a proper form.
-ie: AT91C_BASE_US0 - for usart0,
+i.e.: AT91C_BASE_US0 - for usart0,
AT91C_BASE_US1 - for usart1
... And so on ...
In this case, I'm trying to figure out what USARTs exist.
Step 1 - is to determine if the NAME has been defined.
-ie: Does AT91C_BASE_USx - where X is some number exist?
+i.e.: Does AT91C_BASE_USx - where X is some number exist?
The "info exists VARNAME" tells you if the variable exists. Then -
inside the IF statement... There is another loop. This loop is the
With that little bit of code - I now have a bunch of functions like:
show_US0, show_US1, show_US2, .... etc ...
-
+
And show_US0_MR, show_US0_IMR ... etc...
-
+
And - I have this for every USART... without having to create tons of
boiler plate yucky code.
Code Review / openocd.git / blobdiff