On 29/04/12 02:34, Tarl Neustaedter wrote:
The MS word is suppose to wait a specified amount of milliseconds before allowing a program to continue. Yet when a simple line of code like this is run: "1000 MS ." hi" ", the message is printed immediately. This happens no matter how high the top value on the stack is. Is this a bug or am I missing something?
Looks like a bug. A common one, since there is no generally accepted way of measuring delay inside the Forth engine - we seem to always hand-code a platform-specific method in Openboot (these days we use the "stick" register to measure real time, and have a property to correlate the counter to real nanoseconds).
We've several times had bugs where under some conditions, the measurement of real time differed from virtual time by orders of magnitude - both ways.
It's even worse than that in OpenBIOS:
0 value dummy-msecs
: get-msecs ( -- n ) dummy-msecs dup 1+ to dummy-msecs ;
: ms ( n -- ) get-msecs + begin dup get-msecs < until drop ;
Effectively we just increment the counter every time we call get-msecs, and then just exit after n iterations. If you want something near a concept of real time, I guess you'd have to implement get-msecs for your platform by reading a hardware counter/timer of some description.
HTH,
Mark.