tag:blogger.com,1999:blog-17487316.post5360859924200602480..comments2024-01-13T09:14:12.131+00:00Comments on The life of a Games Programmer: Memory mapped LED's!!Mikehttp://www.blogger.com/profile/15958965170878448339noreply@blogger.comBlogger7125tag:blogger.com,1999:blog-17487316.post-48974074393562697942007-01-12T11:00:00.000+00:002007-01-12T11:00:00.000+00:00Mike!
The userport is bidirectional 8 bits. Only ...Mike!<br /><br />The userport is bidirectional 8 bits. Only the incoming and outgoing values are AND-ed together. So before you want to read an incoming line you should put a 1 bit there. For example if you want to read on all 8 bits, you should put $ff to $fd10 before reading. On write you can write anything for all of the 8 bits and they can be read on the other end.<br />I use my parallel 1541 and a HP LaserJet printer this way.<br /><br />Regards, SizAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-17487316.post-90474027962504484372007-01-09T19:24:00.000+00:002007-01-09T19:24:00.000+00:00Yep, I know that...and I agree. But without a regi...Yep, I know that...and I agree. But without a register to enable you to change it, it doesn't matter! I think its setup like that by default either in the ROM or on the CHIP itself.<br /><br />If the ROM sets it, then yes...once we find the register we can change it...but until then, its fix at 4in, 4 out....Mikehttps://www.blogger.com/profile/15958965170878448339noreply@blogger.comtag:blogger.com,1999:blog-17487316.post-53734823767731449062007-01-09T11:48:00.000+00:002007-01-09T11:48:00.000+00:00Hi Mike!
If the parallel port lines are not bidir...Hi Mike!<br /><br />If the parallel port lines are not bidirectional on your plus/4 then i think the 6529 driving it is broken. I checked on various sites that there are no components between the User Port connector and the 6529, and since the keyboard is read through a 6529 too it must be bidirectional on all its lines.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-17487316.post-19292757389380455152007-01-07T20:27:00.000+00:002007-01-07T20:27:00.000+00:00Had a look through the code....
I currently use $...Had a look through the code....<br /><br />I currently use $fd01/$fd02 for flags (to/from the PC).<br /><br />and $FD10 for 8 bit data transfer - however, the bits appear to be hiredwired to 4out/4in Im looking at the ANCO ref manual, and it doesn't appear to have anything about a data direction register.<br /><br />This means theres only 4 outputs on the +4 parallel port....unless you can find a DDR somewhere... :(Mikehttps://www.blogger.com/profile/15958965170878448339noreply@blogger.comtag:blogger.com,1999:blog-17487316.post-89864143378705774692007-01-07T11:45:00.000+00:002007-01-07T11:45:00.000+00:00You should try to find someone having this book: h...You should try to find someone having this book: http://plus4.emucamp.com/publications.php?pid=400062 or its original: http://plus4.emucamp.com/publications.php?pid=400063 . This is where i read the mentioned examples. Maybe he/she can translate and send you the relevant pages.<br /><br />gerliczerAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-17487316.post-79770733939438027612007-01-07T10:18:00.000+00:002007-01-07T10:18:00.000+00:00Yes there are a few others tied to the RS232 part ...Yes there are a few others tied to the RS232 part I think, but I have no information about using them. <br /><br />I'm comparing to the C64 which has a proper bidirection port that you can toggle with a data direction register. As far as I know, the Plus/4 doesn't have one of these and seems to be fixed to 4 out 4 in. However.... I have VERY little info on these ports, so I could be WAY off.<br /><br /><br />This is about all I can find.<br />http://solder.dyndns.info/pub/files/commodore/plus4/hardware/Service_Manual/17_Userport.pdfMikehttps://www.blogger.com/profile/15958965170878448339noreply@blogger.comtag:blogger.com,1999:blog-17487316.post-13942339855495843672007-01-07T08:35:00.000+00:002007-01-07T08:35:00.000+00:00Hi Mike!
Could you please clarify what this "ther...Hi Mike!<br /><br />Could you please clarify what this "there are only four out lines on the User Port" is? You mentioned this now the second time. I'm sure that i saw in some book one example about driving a parallel port printer and another one about an 8 channel intrusion detector implemented through the User Port.<br /><br />I think you are talking about only the ACIA (6551 - mapped at $FD0x) and forgot that there is also a 6529B (mapped at $FD1x) connected to the port. The latter is an 8 bit parallel bi-directional port. AFAIK paralellized 1541s work on plus/4 also via this.<br /><br />Best regards,<br /><br />gerliczerAnonymousnoreply@blogger.com