johnhlee@cory.Berkeley.EDU (John Lee) (02/09/88)
Help! I'm attempting to interface an IBM compatible 5 1/4" drive (Qume) to my B2000 and mount it internally (where a hard drive will eventually go). I have the Amazing Computing article (vol. #1, issue #4, I think) and after staring at it, it seems easy--too easy! After perusing the Hardware Reference manual, it states (in the appendix, disk connector interface) that Amiga drives has an identification mode that basically goes: 1. Controller asserts SELxB\ 2. Controller asserts MTRxB\ 3. Controller de-asserts MTRxB\ 4. Controller deaserts SELxB\ 5. Begin ID loop. Controller asserts SELxB\ and the drive will respond with the next bit of its ID on RDY\. 6. Controller deasserts SELxB\. Repeat 5-6 until all 32 bits of the drive's ID has been sent, MSB first. 3-1/2" drives are assigned an ID of 0xffffffff and 5-1/4" drives have an ID of 0x55555555. (Signal names may be off, I don't have the manual with me at the minutes, but they can't be confused. the '\' means the signal is active low.) Now the Amazing Computing article's interface doesn't address this ID mode at all, and the vanilla 5-1/4" drives don't have an ID mode. So my question is: Is the ID mode used at all, and can I get away without it? Since the Hardware Reference manual (Addison-Wesley) was made for the A1000 and a very early version at that, perhaps the ID function was ignored under later versions of AmigaDOS. Thanks in advance! John Lee UUCP: ...!ucbvax!cory!johnhlee ARPAnet: johnhlee@cory.Berkeley.EDU
johnhlee@cory.Berkeley.EDU (John Lee) (02/11/88)
(Sorry if you've seen this already, but my previous posting didn't seem to go outside Berkeley.) Help! I'm attempting to interface an IBM compatible 5 1/4" drive (Qume) to my B2000 and mount it internally (where a hard drive will eventually go). I have the Amazing Computing article (vol. #1, issue #4, I think) and after staring at it, it seems easy--too easy! After perusing the Hardware Reference manual, it states (in the appendix, disk connector interface) that Amiga drives has an identification mode that basically goes: 1. Controller asserts SELxB\ 2. Controller asserts MTRxB\ 3. Controller de-asserts MTRxB\ 4. Controller deaserts SELxB\ 5. Begin ID loop. Controller asserts SELxB\ and the drive will respond with the next bit of its ID on RDY\. 6. Controller deasserts SELxB\. Repeat 5-6 until all 32 bits of the drive's ID has been sent, MSB first. 3-1/2" drives are assigned an ID of 0xffffffff and 5-1/4" drives have an ID of 0x55555555. (Signal names may be off, I don't have the manual with me at the minutes, but they can't be confused. the '\' means the signal is active low.) Now the Amazing Computing article's interface doesn't address this ID mode at all, and the vanilla 5-1/4" drives don't have an ID mode. So my question is: Is the ID mode used at all, and can I get away without it? Since the Hardware Reference manual (Addison-Wesley) was made for the A1000 and a very early version at that, perhaps the ID function was ignored under later versions of AmigaDOS. Thanks in advance! John Lee UUCP: ...!ucbvax!cory!johnhlee ARPAnet: johnhlee@cory.Berkeley.EDU
ssd@sugar.UUCP (Scott Denham) (03/05/88)
In article <624@pasteur.Berkeley.Edu>, johnhlee@cory.Berkeley.EDU (John Lee) writes: > Help! I'm attempting to interface an IBM compatible 5 1/4" drive (Qume) > to my B2000 and mount it internally (where a hard drive will eventually go). > I have the Amazing Computing article (vol. #1, issue #4, I think) and after > staring at it, it seems easy--too easy! After perusing the Hardware > Reference manual, it states (in the appendix, disk connector interface) that (descripton of signal names deleted) > my question is: Is the ID mode used at all, and can I get away without > it? Since the Hardware Reference manual (Addison-Wesley) was made for > the A1000 and a very early version at that, perhaps the ID function was > ignored under later versions of AmigaDOS. Thanks in advance! > > John Lee > In a word, no. The ID's gotta be there if you want to use the drive as a) a half-sized Amiga DOS drive (I.E. you MOUNT it) or b) with the utilities provided on the 1.2 disk. I don't know about DOS-2-DOS or Transformer; I'd assume Transformer would work, since that's the environment for which the Amazing Computing article was intended. You can do the ID mode with the other side of the '74 you already have for a motor latch - there are a couple of circuit descriptions floating about on how to do this. The current versions of the OS are picky indeed about this ID, and if it isn't there, than neither is the disk drive! It also gets unhappy if you get your flips and flops wrong trying to generate it! (voice of experience) Scott Denham