Hand Held Products 71M/M eprom carrier question

[coitboy2000]

(06-13-2020 11:25 PM)cmurillo Wrote:  I did not find the messages right away, but I did figure what the required format is; nibbles must be swapped _and_ negated, so that a nibble sequence like

B3DDDDDEE4642513

must be written as a sequence of bytes in the EPROM as

C4 22 22 12 B1 B9 AD CE

carlos.

What is the easiest way to flip each bit ? I can manage to invert the bits in a hex editor but flipping/reversing each bit seems to be a challenge.

Regards

Richard