6 units: Fairchild, 74F157A - High-speed Quad 2-Input Multiplexer

3 units: Texas Instruments, SN74LS193N - Synchronous 4-Bit Counter (PDIP)

3 units: National Semi, DM74LS173N - 4-Bit D-Type Register (Tri-State)

12 units: National Semi, DM74LS125N - Quad TTL Bus Buffer (PDIP14, 4-Bit)

5 units: Fairchild, 74ACT240 - Octal Inverting Buffer/Line Driver 3-State

6 units: Motorola, SN74LS157N - Quad 2-input Multiplexer (4 Bit Data Select)

4 units: Motorola, 74LS00 - Quad 2-input NAND gate

19 units: Texas Instruments, SN74S169N - Synchronous 4-bit Up/Down Counter