DELTA TAU ACC-72E Input/Output Module Conversion Board

This parameter controls how many lines ahead of the executing line the host can provide a ACC-72E rotary motion program buffer before it signals that it is not ready for more lines (BREQ line held low, coordinate system status bit Rotary Buffer Full becomes 1). This status information can be detected either by polling ?? or PR, by using the interrupt line to the host, or by polling the status register of the interrupt controller. If you send a program line to the rotary buffer, the BREQ line will be taken low (at least momentarily). If there are still fewer than I17 number of lines in the buffer ahead of the executing line, the BREQ line will be taken high again (giving the ability to generate an interrupt), and the Rotary Buffer Full status bit will stay 0. If there are greater than or equal to I17 lines in the buffer ahead of the executing line, the BREQ line will be left low, and the Rotary Buffer Full status bit will become 1. Normally at this point, the host will stop sending program lines (although this is not required) and wait for program execution to catch up to within I16 lines and take BREQ high again.