I was disappointed to find errors in the code for the Real Time Clock and New Character Sets (just the things for my all singing and dancing WYSIWIG word processor) in the birthday issue. First the New Character Set wouldn't work at all , so out with the disassembler. I found three rst 08 calls to location 1400 in the lower ROM - the routine which prints characters to the screen. Now I have a 664 (yes, some people did buy them), which has Basic 1.1. For my machine the location of this routine is 13FA. So for all those 664 and 6128 owners, change all 00, 94 pairs in the listing to FA, 93. Direct calling of routines in the ROMs is a big naughty. One should make copies of the actual machine jump blocks. Then the 464/664/6128 ROM changes do not cause problems. Secondly, the Real Time Clock resets the machine at midnight and jumps forward seven minutes at every hour. So for all those Cinderellas who don't wish to be caught out I have made the following changes:
230 DATA 9C3CFE18CC538032429C3E07CD5AF 240 DATA 5AB83E00C93E0CC93E06CD1EBB5CD I was pleasantly surprised to find this routine keeps good time in spite of many disk accesses.Simon Kidd, Malvern. Many thanks to all those who sent in corrections to the Real Time Clock.. This one was presented purely on terms of content but I'm sure that there's hundreds of CPC experts out there. AA n°40 |