>C=N RM=80 LM=3 TM=1 BM=66 J=N             DPU3 - 74S244  Buffer (Must be 74S244 only)       Fig. 3                        8  | \  12                                                 Pin U32-15  >-------|  -----|---------> R7   ( Remember to cut the trace     Clock              |/      |     Clock     at U32  pin 5 )                                             |     This buffer replaces U32 for Clock                         17 |\  3   |                                               HD64180 - 64>-------|  -----|                                                Clock              |/                                                                                                                                                   2  |\  18                                                  U46-5       >-------|  ----|----------> U18-5                                Mux  Z80H          |/     |                Mux line for Rams                                          |    This buffer replaces U18 for Mux                             15 |\  5  |                                                U46P-5      >-------|  ----|                                                 Mux HD64180        |/                                                                                                                                                   4  |\  16                                                  Z80 Cpu - 27>-------|  ----|----------> Z80 Socket pin 27                    M1                 |/     |                M1                                                         |    This buffer is added because M1 & LIR                        13 |\  7  | don't TRI-STATE                                HD64180 - 61>-------|  ----|                                                 LIR                |/                                                                                                                                                   6  |\  14                                                  Z80 Cpu - 18>-------|  ----|----------> Z80 Socket pin 18                    Halt               |/     |                Halt                                                       |    This buffer added because Halt doesn't                       11 |\  9  | TRI-STATE                                      HD64180 - 56>-------|  ----|                                                 Halt               |/                                                                                                                                                   2  |-------| 5                                             U48-2       >-------|D     Q|--------> DUP3-17 Mux                                              | U46P  |     This Chip is Piggy Backed on U46                           3  |       | 4  with All pins bent up except 7,14,4        Clock       >-------|CK     |----> U46-4                                    HD64180             |---|---|   The Mux circuit is VERY crankey so we  will                         | 1  duplicate for the HD64180 so all timming edges                         |    come out the same. A must for 6.667/6.144 Mhz                          |-------> DPU1-57 Refsh Hd64180                      