info-vax@ucbvax.ARPA (04/08/85)
From: spracklin@EDWARDS-VAX HELP! I am a DEC software type on Edwards AFB where we use the RANYAN Peripheral Processor Link (PPL-2) which is a Q-bus/UNIBUS interface to com- municate between an LSI 11/23 and a VAX 11/780. The current configuration utilizes the LSI hosted memory capability (the physical memory is on the LSI) which basically performs DMA operations on the LSI side into the memory and performs Programmed I/O (PIO) on the VAX side. There is no software required on the LSI , whereas the VAX software consists of Create Map Section (CRMPSC) to the UNIBUS addresses controlled by the VAX-RANYAN PIO board. Communication consists of memory moves from the UNIBUS address into VAX local memory at an approximate cost of 10 micro-secs per word. An effort is aimed at achieving a VAX hosted memory capability , in particular to develop the software to support the VAX hosted RANYAN DMA board. To allow the DMA transfer into the VAX memory window it is required to set up the UNIBUS mapping registers and data path(s) related to the transfer. The hardware has been checked out with a logic analyzer and we seem to be talking to the UBA from the RANYAN DMA board correctly , yet the two software techniques discussed below have yet to transfer a bit. (Excuse the pun?!?) 1. CRMPSC/Connect to Interupt approach which sets up the UBA at the initialization entry of CONINTERR. 2. A full driver entered via QIO with a timeout of 65355 seconds which should allow transfers until the device interrupts. Since the RANYAN transfers generally without interrupts this is ideal since we are in a demanding real-time environment. I have been in contact with the president of RANYAN here in Huntington Beach and he is unaware of any software to support the VAX host capability. Does anyone have any experience , knowledge of a site using a VAX hosted RANYAN , or any ideas ? Thanks in advance. Regards, Darrell Spracklin (805)-277-3864