I'm having fun with some 74LS283[1] 4 bit binary adders but I am having trouble working out how I should convert the output to a decimal which could be used to drive two 7 segement displays which are powered by 74LS47s.

The adder outputs correctly 0001 + 0010 = 0011 but I'm not sure of the best way to approach converting this to BCD to drive my displays. Could someone tell me the best approach for this?



[1] http://www.ti.com/lit/ds/symlink/sn74ls283.pdf

[2] http://www.ti.com/lit/ds/symlink/sn74ls47.pdf

  • \$\begingroup\$ Do a Google search for TTL binary to BCD. \$\endgroup\$ – RoyC Mar 18 '17 at 11:22
  • \$\begingroup\$ I also seem to remember a binary to several digits of seven segment decoder at some point in the distant past, it was for driving LED seven segments. \$\endgroup\$ – RoyC Mar 18 '17 at 11:29
  • \$\begingroup\$ In general, if you want a decimal display, it's best to do the internal logic in BCD rather than straight binary, because implementing binary-to-BCD conversion as a separate step is rather expensive in terms of logic. \$\endgroup\$ – Dave Tweed Mar 18 '17 at 13:27

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