jxh@cup.portal.com (05/19/88)
(cross-posted from comp.sys.sun) Having heard rumors of the existence of the Sun Multiprotocol Communications Processor (MCP) which, I presume, is a VME board that does BOP (SDLC) at relatively high speeds (I need at least 1Mbit/s; 2.4Mb/s would be nice), I have the following problem: I intend to use a Sun386i, which is not a VME machine. It has PC-AT-like slots. Does anyone know of a PC I/O Channel card that performs this function? I am using an AST CC-232-E, but it needs an interrupt per character, which is limited by the interrupt latency of the machine. This means about 9.6Kb/s on an AT&T PC 6300, perhaps 19.2Kb/s on a 6MHz AT clone. Here are my requirements: - Ability to send and receive SDLC frames at 2.4Mb/s (b=bit, B=byte). This entails: - On-board processor - Dual-port RAM - DMA from the serial chip into the first stage of memory - Ability to pass frames to the host processor using I/O Channel DMA -or- On-board memory mapped into I/O Channel memory space (DMA preferred) - RS-232 or RS-422/423 (232 preferred) I have heard of SeaLevel, AST, and Tecmar. SeaLevel makes such a board with RS-423; AST doesn't do DMA; Tecmar doesn't appear to have anything fast either. Where are the rest of them? Does anyone on the net have any experience with one? How much did it cost? (just curiousity: cost is virtually no object, compared to the rest of the system it's going into) I saw one from some outfit in Georgia that might fit the bill, but I'd like to specify a stable vendor if it is to be the sole source, and I can't remember their name. Please email me any information you have. If interest is high, I'll summarize to the net. Thanks very much. P.S. This is going to comp.sys.ibm.pc, as well as Sun-Spots. Jim Hickstein, VSAT Systems, San Jose, CA (408) 435-8016 jxh@cup.portal.com ...!sun!portal!cup.portal.com!jxh