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Operations: # (binary to BCD), $ (BCD to binary)

A project log for Bit-serial CPU based on crossbar switch

256 switches and few shift registers to implement a working 16 or 32-bit integer arithmetic calculator (+, -, *, /, isqrt, BCD / bin conv..)

zpekiczpekic 04/27/2022 at 05:130 Comments

Algorithm used:

Both of these use adjacent shift registers and 1 - bit shift and (optional) correction steps which make them convenient for serial CPU.

# - TOS (BCD) <= TOS (binary)

(refer to microcode lines 419-448 , more details to come...)

$ - TOS (binary) <= TOS (BCD)

(refer to microcode lines 394-414 , more details to come...)

Example: converting 9999 to 270F and vice versa

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