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elektrownik
January 7th, 2014, 09:42 AM
I have question about RTC configuration. I own MT-881 I/O card with RTC onboard. I replaced old battery but I want to set correct time and date. Identical situation has been described here: http://www.vintage-computer.com/vcforum/archive/index.php/t-22535.html Unfortunatly I have no ability to transfer any external files to my XT 5160 clone so I want to do this with DEBUG. At this point RTC isnt working correct, whatever I read (hours, minuts, seconds) it return 48, also I couldnt find commands to write to RTC. Can anyone help me ? Thanks
PS: to read data from RTC I'm using "-o 70 xx" and "-i 71" where xx is number of value to return (hours, seconds, etc.)

elektrownik
January 7th, 2014, 10:39 PM
I have question about RTC configuration. I own MT-881 I/O card with RTC onboard. I replaced old battery but I want to set correct time and date. Identical situation has been described here: http://www.vintage-computer.com/vcforum/archive/index.php/t-22535.html Unfortunatly I have no ability to transfer any external files to my XT 5160 clone so I want to do this with DEBUG. At this point RTC isnt working correct, whatever I read (hours, minuts, seconds) it return 48, also I couldnt find commands to write to RTC. Can anyone help me ? Thanks
PS: to read data from RTC I'm using "-o 70 xx" and "-i 71" where xx is number of value to return (hours, seconds, etc.)
This topic is useless because I finally connected 5"25 diskette drive to my new PC and it works fine so I can copy files to my old PC without problem now. I set RTC and it is working. Still I dont know why I couldnt set it via assembler in/out or debug -i/-o but TIMER app done this correct. Now I'm going to run mail/internet on my 27 years XT PC, I have 8bit ISA modem, I set it to COM2 and it is detected by SERIAL app :)

modem7
January 7th, 2014, 10:47 PM
PS: to read data from RTC I'm using "-o 70 xx" and "-i 71" where xx is number of value to return (hours, seconds, etc.)
Those ports are for AT-class computers.

For XT-class computers, there was no standard. The card makers did what they wanted. For example, AST used ports that start at 2C0 (refer [here (http://www.minuszerodegrees.net/misc/AST_TB-052.txt)]). Because there is no standard, not only do you need to work out the port range for your card, but you also need to work out the commands. The commands should be in the datasheet for the RTC chip used on the card.

It will probably be simpler to get file transfers working to your computer (so that you can load the driver).

Chuck(G)
January 8th, 2014, 09:36 AM
...and those old multi-I/O cards usually used an Oki chip for the clock, not the Motorola chip, so that interfacing is completely different from the clock chip in an AT or later.