jeffj@pro-avalon.cts.COM (Jeff Jungblut) (09/16/88)
----- Forwarded Message ----- From: tomk (Tom Kelly) I am attempting to upgrade my Apple ][ computer. The case says it is an Apple ][+ but I have my doubts about that. It has a Rev. 4 motherboard. In location A5 it has a 2513 chip rather than a 2316B. It has 48k of RAM and configuration blocks on the motherboard. These two things cause me to suspect it may actually be an Apple ][. I would like to expand it to 64k. I installed a known good 16k RAM card (from an Apple ][+ ) in slot 0. I removed the chip from E3 and put it on the RAM card. I plugged the ribbon cable from the RAM card into the E3 socket . Both ends of the cable were installed properly. All RAM chips have been verified to be good. When I run a test of the memory, the 48k checks good but the extra 16k checks bad. If I put the RAM card back in my other Apple ][+ the extra 16k checks good. Is there something special I need to do because I have a REV. 4 motherboard? I would also like to get lower case characters. The problem is I can't just plug in the chip that is used in my other Apple ][+ (a specially programmed 2716 EPROM) because the pinout of a 2513 isn't the same as a 2316B and 2716. How can I get lower case without getting an 80 column card? If anyone can help me with these problems, I will be very grateful. I can do the work if someone will tell me what needs to be done. ********** Thanks in advance. ** Tom ** Tom Kelly (tomk@pro-avalon.cts.com)
drich@bgsuvax.UUCP (Daniel Rich) (09/16/88)
Since I may be one of the last remaining Apple ][/][+ techies still using my computer :-), I will see if I can answer your questions.... (I will warn you though, this is all from memory, my manuals are back at my aparment.) From article <8809152358.AA09359@crash.cts.com>, by jeffj@pro-avalon.cts.COM (Jeff Jungblut): > ----- Forwarded Message ----- > From: tomk (Tom Kelly) > > I am attempting to upgrade my Apple ][ computer. > The case says it is an Apple ][+ but I have my doubts about that. As long as your computer has Applesoft Basic installed on the motherboard, it is a ][+. > It has a Rev. 4 motherboard. ... description of the motherboard ... > These two things cause me to suspect it may actually be an Apple ][. It has been a long time since I have seen an Apple with less than a rev 7. It sounds like your board is closer to the rev 0 talked about in the Reference Manual. > I would like to expand it to 64k. I installed a > known good 16k RAM card (from an Apple ][+ ) in slot 0. ... installation and testing description ... > ...Is there something special I need to do because I have a REV. 4 > motherboard? I would suggest putting the 16K card into your computer and then booting with your system master. If it loads integer basic correctly, than you have a working card. You might also want to try any other programs you have that access the card. Remember on the ][+, you can never truly have 64K. The expansion memory is bank switched into the same locations as the Applesoft Basic roms. > I would also like to > get lower case characters. The problem is I can't just plug in the chip > that is used in my other Apple ][+ (a specially programmed 2716 EPROM) > because the pinout of a 2513 isn't the same as a 2316B and 2716. > How can I get lower case without getting an 80 column card? This one is tricky. My best suggestion (having never dealt with a rev 4 motherboard) would be to find an EPROM with the same pinout as the 2316B. Then have someone copy your 2716 onto it. > If anyone can help me with these problems, I will be very grateful. > I can do the work if someone will tell me what needs to be done. > ********** Thanks in advance. ** Tom ** > > Tom Kelly (tomk@pro-avalon.cts.com) That sounds like it should do it....(I hope) Just remember, I have never dealt with a rev 4 motherboard. I am assuming that it is more like a rev 0 then the rev 7 I am used to. - Dan Rich UUCP: ...!osu-cis!bgsuvax!drich CSNET: drich@andy.bgsu.edu PHONE: (419) 372-6002 - Shift to the left! Shift to the right! Pop up! Push down! Byte, Byte, Byte! -
marc@lakesys.UUCP (Marc Rassbach) (09/18/88)
Comment on 2716/9316B replacment. You will need to add an inverter to the 2716 and jumper two pins, else you WILL fry the ][+. The pins to mod are: 21 to 24 19 to 24 Correction 18 to the inverter, and you take the input for the buffer from pin 18 on the motherboard. You don't do anything with pin 19.