stevef@well.UUCP (Steven Robert Fordyce) (08/16/89)
> I can report a success story at installing the CMI accelator board. [STuff deleted] > One question... the red fly-wire, documentated as connected to R4 > on the 520st, and un-connected on the Mega-st... what is its purpose? > At least for me, the board seems to work regardless of whether or not > the red wire is connected. My copy of the st schematics (which admittedly > might not match the motherboard revision I have) shows R4 as being in > the midi data current loop circuitry. This is the interupt for the blitter. That's why it isn't needed on a Mega, which already has a blitter. Of course, it is only needed on a 520, or 1040 if a blitter is installed on our board. > A note on the manual... the way I read it it implies that you get 16mhz > operation by closing the jumper, and 8mhz by leaving it open. However > on my system it's just the opposite; 8mhz when the jumper is closed, > 16mhz when it's open. What you said is correct: the manual is in error. Sorry! We are currently rewriting the manual. > What are the recommended parts to use the fastrom sockets directly on the > board? Standard 1 megabit (128k x 8), 200 ns or faster parts. These will be available from us programed with 1.4 as soon as we get a license from Atari, which we expect real soon now. > What is the definition of the "expansion" pins? We will be anouncing an expansion product that will plug into that when we are done with it. But in any case, here is the pinout: Pin Definition 1 +5 2 A04 3 A03 4 A02 5 A01 6 EN1* 7 EN2* 8 UDS* 9 LDS* 10 AS* 11 DTACK* 12 GND 13 GND 14 GNB 15 NC 16 D00 17 GND 18 +5 19 D01 20 D02 21 D03 22 D04 23 D05 24 D06 25 D07 26 FC0 27 FC1 28 FC2 29 IPL0* 30 IPL2* 31 RESET* 32 READ 33 8M 34 GND If this seems like an odd collection of signals, it is because we had a specific purpose in mind for the connector and we included only those signals we needed for that purpose. The row of pins starting with the pin closest to the CPU are numbered 1-17. The next row is 18-34, with pin 34 next to pin one. EN1 and EN2 are two decoded addresses. 8M is a buffered 8 MHz clock. By the way, the 1040 version of our board will be shipping next week. Steven R Fordyce uunet!sequent!calvin!stevef Creative Microsystems, Inc., 19552 SW 90th Court, Tualatin, Oregon 97062, USA For customer service, call Lillian Carter at (503)691-2552, FAX (503)691-1292