slp9m@cc.usu.edu (Scott E. Parker) (06/27/91)
I need to get data from a VME bus based machine into a Mac II as fast as possible. I have seen (but can't remember where) cards that let macs arbitrate for and read from the VME bus directly. Can anyone provide references? Is this the way to go? What other options exist? Pros & cons? I'm open to all comments and suggestions. The following two paragraphs are supplimentary reading for potential respondants who would like more back- ground on the actual problem. Advance thanks -SEP I need to speed up communications between a mac and a custom built VME bus machine and am open to suggestions on the best approach. The VME bus machine is a radar used for middle and upper atmospheric research and thus will be refered to hereafter as "the radar". The situation is this: The radar can be viewed as a very proficient data generator. The actual data rate depends on the mode of operation, but the last campaign it was involved in it was churning out 8000 bytes/sec of data. This was in a rather slow mode. The Mac's function is to take this data and produce graphics in real time. Since the data is recorded on tape and analyzed after the fact, the mac has in the past been a rather low priority. The only means of communication between the two devices until now has been a serial line at 56 kbaud (read: bottleneck). ############################################################################ # Scott E. Parker # INTERNET: SLP9M@cc.usu.edu # # Center for Atmospheric & Space Science # Twisted pair: (801) 750-2975 # # Utah State University # Home: (801) 753-3924 # # Logan, UT 84322-4405 # # ############################################################################
michael@mcdchg.chg.mcd.mot.com (Michael Bodine) (06/27/91)
Scott E. Parker (slp9m@cc.usu.edu) writes: > I need to get data from a VME bus based machine into a Mac II as fast as > possible. I have seen (but can't remember where) cards that let macs > arbitrate for and read from the VME bus directly. Can anyone provide > references? Is this the way to go? What other options exist? Pros & cons? VME to Nubus cards can be purchased from: Bit3 Computer 8120 Penn Ave S Minneapolis, Mn 55431 (612) 881-6955 Their model 453 board allows the MacII to access VMEbus memory directly. There are other vendors of such boards, but i don't have their address/phone readily available. We have customers who have used other Bit3 products successfully, tho' none using this particular board. Another method is to put your VME chassis on the same SCSI bus as the MacII and its disk drive, then to do your communications via SCSI transactions. Motorola has the MVME147 series of cpus that have built-in SCSI support that have been used in this way. Probably your choice would depend on the required data rate, ease of programming and cost considerations. -- [ Michael Bodine, michael@chg.mcd.mot.com, Dial: (708) 576-7840, FAX: x8875 ] [ Motorola TSD; Loc IL38; 1100 Woodfield; Suite 334; Schaumburg, Il 60173 ]