# Vacuum Tube Computer Part 35: Output Register—a One-Byte Write-Only Memory

**URL:** <https://scanalyst.fourmilab.ch/t/vacuum-tube-computer-part-35-output-register-a-one-byte-write-only-memory/4090>\
**Category:** Continuity\
**Tags:** computing, vacuum-tube, input-output\
**Created:** [11 December 2023 13:12 UTC](https://scanalyst.fourmilab.ch/t/vacuum-tube-computer-part-35-output-register-a-one-byte-write-only-memory/4090 "2023-12-11T13:12:13Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![johnwalker](https://scanalyst.fourmilab.ch/user_avatar/scanalyst.fourmilab.ch/johnwalker/32/17415_2.png) [@johnwalker](https://scanalyst.fourmilab.ch/u/johnwalker)\
**Post date:** [11 December 2023 13:12 UTC](https://scanalyst.fourmilab.ch/t/vacuum-tube-computer-part-35-output-register-a-one-byte-write-only-memory/4090/1 "2023-12-11T13:12:13Z")

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[![](https://scanalyst.fourmilab.ch/uploads/default/original/3X/d/3/d399ae3c4a2df9e36b29459670d08572abeb7020.jpeg "VTC P.35 – Building the Output Register") ](https://www.youtube.com/watch?v=B46wuLBvPDk)

Output from the one-bit vacuum tube computer is sent to an 8-bit addressable output register, where it is stored and can be sent to external devices. Since the output register cannot be read by the computer, it is genuinely write-only memory. Building the register’s flip-flops with vacuum fluorescent displays as one of their tubes integrates display of the output’s state with its storage.