On Sun, Jan 30, 2022 at 11:43 AM Chris Zach via cctalk <cctalk@classiccmp.org> wrote: > > From the books, the kmc11 had an "lsi11 on board", 1k of 16 bit ram, 1k > of 8 bit data memory a 300ns cycle time, 16 bit microprossor with a 16 > bit micro-instruction bus and 8 bit data path. This is according to the > 1980 Terminal and Communications handbook, so it's a few years after the > 1976 timeframe of Sha Tin. > > Now the original LSI11 processor was 4 main chips, an EIS/FIS chip (or > the CIS lite chip or the weird 1k*20 bit micro-ram board which I have > somewhere). The DCT11 was a single chip lsi11 that had an 8 or 16 bit > outside bus and a 16 bit internal structure and ran pdp11 instructions. > So the KMC11 probably had the DCT11 chip. > > The LSI11 chipset was around in 1975, so it makes sense that DEC could > use it. The SBC11/21 came out in 1981 but the chip was probably avail > internally by 1980 so I'm guessing that the KMC11 and the COMM-IO-DP was > using the DCT11. >
http://www.bitsavers.org/pdf/dec/unibus/MP01118_KMC11B_EngrDrws.pdf KMC11-B Field Maintenance Print Set The KMC11-B used a custom bit-slice processor implementation. (3x) 93S16 4-bit counters for a 12-bit program counter (2x) 74S181 4-bit ALUs for an 8-bit ALU (2x) 74S189 16x4 RAM for 16 8-bit working registers
