sentences:  This co-processor connected to a V80 via a dedicated bus, to a V60 or V70 via a shared main bus, which constrained peak performance.The V60/V70/V80 shared a basic architecture.They had thirty-two 32-bit general-purpose registers, with the last three of them commonly used as stack pointer, frame pointer, and argument pointer, which well matched high level language compilers' calling conventions.