Post by thread:[PIC]Definition of CALL?

I have a question about the definition of the CALL instruction(on the '74 if that makes any difference). I have read in the MICROCHIP data book that the instruction "CALL K" would be valid as long as K is not zero and is less than 2048. In the Parallax documentation, it says that: " The ninth bit of the program counter will be cleared to 0. Therefore, calls are only allowed to the first half of any 512-word page, although the CALL instruction can be anywhere." Which is correct? There is no mention of clearing the ninth bit in the MICROCHIP manual. If the Parallax manual is correct, than I have another question. How can one find out where there program's instructions are positioned in memory. I looked at the .LST file created by the Parallax assembler, but I was not sure if the hex numbers numbers (the second column) where the actual position of each instruction. It does not appear so because because it lists all of the ram declarations (example: ram_space ds 1) as actual instructions. I assumed that the ram declarations where strictly for the assembler and were not actual code. Thanks in advance Zach Radding PS I have been getting weird anomalies in my programs, but I just re-arrange my functions being called and then everything works. I want to know why.

Xaq <spam_OUTxaqTakeThisOuTINDIRECT.COM> wrote: > In the Parallax documentation, it says that: > " The ninth bit of the program counter will be cleared to 0. Therefore, > calls are only allowed to the first half of any 512-word page, although the > CALL instruction can be anywhere." > > Which is correct? There is no mention of clearing the ninth bit in the > MICROCHIP manual. This clearing of the bit applies only to the 16C5x chips, not the 16C74 or any other 16C6x or 7x chips. Clyde -- Clyde Smith-Stubbs | HI-TECH Software, | Voice: +61 7 3300 5011 .....clydeKILLspam@spam@hitech.com.au | P.O. Box 103, Alderley, | Fax: +61 7 3300 5246 http://www.hitech.com.au | QLD, 4051, AUSTRALIA. | BBS: +61 7 3300 5235 ---------------------------------------------------------------------------- For info on the World's best C cross compilers for embedded systems, point your WWW browser at http://www.hitech.com.au, or email infoKILLspamhitech.com.au