; JED2EQN -- JEDEC file to Boolean Equations disassembler (Version V063) ; Copyright (c) National Semiconductor Corporation 1990-1993 ; Disassembled from J070-U9.jed. Date: 2022-05-28 ; ; Initial analysis: not tested yet! ; chip J070-U9 PAL16R6 ; ; STEbus arbiter and interface control. ; CLK = 1 ; BR0 = 2 ; STE bus request 0 BR1 = 3 ; STE bus request 1 BA = 4 ; from microprocessor BS = 5 ; from microprocessor T1 = 6 ; Timeout signal QM = 7 ; Q from microprocessor TRF = 8 ; STEbus transfer error RNW = 9 ; read not write GND = 10 ; /OE = 11 ; tied low, to permanently enable outputs. /READ = 12 ; /OE of memory chips /HALT = 13 ; halt to CPU /BG0 = 14 ; STE bus grant 0 /BG1 = 15 ; STE bus grant 1 /NMI = 16 ; non-maskable interrupt /WE = 17 ; /WE of RAM chips /BRST = 19 ; STEbus reset VCC = 20 equations BRST = BRST WE := QM * /RNW NMI := /BRST * NMI * BA + /BRST * NMI * /BS + /BRST * NMI * /QM + /BRST * T1 ; timeout + /BRST * /BG1 * /BG0 * TRF ; STEbus transfer error ; ; STEbus arbiter: ; BG1 := /BRST * BR1 * BG1 + /BRST * BR1 * /BR0 * BA * BS * QM * HALT BG0 := /BRST * BR0 * BG0 + /BRST * BR0 * /BG1 * BA * BS * QM * HALT HALT := BR0 * HALT + BR1 * HALT + BR0 * /BA * QM + BR0 * /BS * QM + BR1 * /BA * QM + BR1 * /BS * QM READ = RNW /BRST.oe = gnd /WE.oe = OE /NMI.oe = OE /BG1.oe = OE /BG0.oe = OE /HALT.oe = OE /READ.oe = vcc