On Thu, Oct 25, 2018 at 11:45 AM Chuck Guzis via cctalk < cctalk at classiccmp.org> wrote: > Didn't at least one of the more popular MPU designs employ a serial ALU? > TMS9900? > I don't think the TI TMS9900 was bit-serial internally, but the RCA CDP1802 and National Semiconductor SC/MP (ISP-8A/500) and SC/MP II (ISP-8A/600) were.