Re: [WP-34s] number display in program mode Message #7 Posted by Paul Dale on 8 Apr 2012, 4:08 a.m., in response to message #6 by Marcus von Cube, Germany
It would be possible to allow numbers and alpha strings as a single statement but we'd have to rework the back step in program mode completely. We'd also have to rework numeric and alpha entry completely -- if somebody is keen, feel free -- your changes would almost certainly be included.
At the moment op-codes are two bytes generally and the alpha argument commands (solve, integrate, triple alpha, ...) are four bytes with the first two byte word starting 0xF000 - 0xFF00. This scheme is entirely my fault after much pushing by Walter for better labels than 00 - 99 plus A, B, C & D. This weird encoding makes stepping backwards easy -- we need this for BST, BACK and BSRB.
Extending this to longer sequences is certainly possible but given the pain adding double word instructions caused (lots), I'd prefer to delay this to the 43S.
A side effect of this is that characters 0xF0 - 0xFF cannot be in the final position of triple-alpha commands. This isn't a significant failing IMO -- nobody has noticed and commented thus far. Comments about this from now on will be studiously ignored of course :-)
- Pauli
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