DIY Paper Tape Punch - Mechanism diagram?

Torfinn Ingolfsen tingox at
Sat May 2 06:14:43 CDT 2020

On Fri, May 1, 2020 at 7:32 PM Tony Duell via cctalk
<cctalk at> wrote:
> As far as I know the 5-hole side is always the most significant 5
> bits, the 3 hole side the least significant 3 bits. In other words the
> holes go :
> 76543S210
> Where S is the sprocket hole and a digit is the bit number (bit 0 is
> the least significant bit).
> As to which way use the tape, with the tape feeding towards you, the
> sprocket hole is normally offset towards the right, that is the bits
> would read with the MSB on the left. I am not sure if that is
> universal though

FWIW, the ECMA standard is here
(found via Wikipedia)

Torfinn Ingolfsen

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