Written by Herb Johnson and Dwight Elvey, last edit Feb 10 2008. My thanks to Dwight Elvey for his programs and his work to re-engineer, restore and program Dr. John Torode's & Digital Systems Inc.'s FDC-1 controller. The description of Dr. Torode's floppy controller is on this linked page.
The following are microcode instructions from the DS microcontroller. These were named by Dwight Elvey using the signals named on sheet #1 of the DS FDC-1. A descripion of the microcode instruction set is on this linked page. I've slightly edited the file Dwight sent me.- Herb Johnson
Main Code 00 F3 SETCNTD 01 47 JN(READY) 02 00 03 0D J(RST) 04 0D 05 48 J(RD) 06 25 07 49 J(WR) 08 25 09 40 JMP 0A 00 0B C3 CLRDMAD 0C 0C JN(SRDY) 0D 0C 0E 0B J(TRK0) 0F 14 10 F4 CLRBRDY 11 C2 SETSTP 12 40 JMP 13 0B 14 C4 CLRDAT 15 C5 CNTDAT 16 43 JN(IDAM) 17 16 18 F4 CLRBRDY 19 F0 CLRCRC 1A 80 LDCNT 1B 01 1C 04 JN(CNT) 1D 1C 1E F4 CLRBRDY 1F 01 JN(EQ) 20 16 21 C6 DCRDMAD 22 40 JMP 23 41 24 C6 DCRDMAD 25 FD DMARD 26 4A J(MAC) 27 26 28 0A JN(MAC) 29 28 2A C7 INRDMAD 2B 43 JN(IDAM) 2C 2D 2D F4 CLRBRDY 2E F0 CLRCRC 2F 06 JN(BRDY) 30 2F 31 F4 CLRBRDY 32 01 JN(EQ) 33 83 34 FD DMARD 35 4A J(MAC) 36 35 37 0A JN(MAC) 38 37 39 06 JN(BRDY) 3A 39 3B 46 J(BRDY) 3C 3B 3D F4 CLRBRDY 3E 01 JN(EQ) 3F 24 40 C7 INRDMAD 41 80 LDCNT 42 01 43 04 JN(CNT) 44 43 45 46 J(BRDY) 46 45 47 45 JN(OK) 48 77 49 06 JN(BRDY) 4A 49 4B F4 CLRBRDY 4C F2 SETCNTC 4D 49 J(WR) 4E 94 4F 80 LDCNT 50 06 51 04 JN(CNT) 52 51 53 F3 SETCNTD 54 03 J(IDAM) 55 8C 56 02 JN(DAM) 57 54 58 F4 CLRBRDY 59 F0 CLRCRC 5A 80 LDCNT 5B 7F 5C FE DMAWR 5D 4C J(SRDY) 5E 5D 5F 0A JN(MAC) 60 5F 61 C7 INRDMAD 62 46 J(BRDY) 63 90 64 44 J(CNT) 65 6B 66 06 JN(BRDY) 67 66 68 F4 CLRBRDY 69 40 JMP 6A 5C 6B 06 JN(BRDY) 6C 6D 6D 46 J(BRDY) 6E 6D 6F FF ZERODBIT 70 06 JN(BRDY) 71 70 72 45 JN(OK) 73 7E 74 FC SETIOF 75 40 JMP 76 00 77 0D J(RST) 78 00 79 FB SETICE 7A 48 J(RD) 7B 4B 7C 40 JMP 7D 74 7E 0D J(RST) 7F 00 80 FA SETDCE 81 40 JMP 82 74 83 F9 SETTER 84 C7 INRDMAD 85 FE DMAWR 86 4A J(MAC) 87 86 88 0A JN(MAC) 89 88 8A 40 JMP 8B 74 8C FD DMARD 8D F9 SETTER 8E 40 JMP 8F 74 90 FA SETDCE 91 F9 SETTER 92 40 JMP 93 74 94 80 LDCNT 95 04 96 04 JN(CNT) 97 96 98 F7 SETWG 99 F4 CLRBRDY 9A F8 CLRDSR 9B C4 CLRDAT 9C 80 LDCNT 9D 02 9E 04 JN(CNT) 9F 9E A0 FD DMARD A1 4A J(MAC) A2 A1 A3 0A JN(MAC) A4 A3 A5 C7 INRDMAD A6 F5 SETCLK0 A7 46 J(BRDY) A8 A7 A9 F7 SETWG AA F0 CLRCRC AB 80 LDCNT AC 7F AD FD DMARD AE 4A J(MAC) AF AE B0 0A JN(MAC) B1 B0 B2 C7 INRDMAD B3 46 J(BRDY) B4 90 B5 06 JN(BRDY) B6 B5 B7 F4 CLRBRDY B8 04 JN(CNT) B9 AD BA C4 CLRDAT BB C1 DCRDAT BC 06 JN(BRDY) BD BC BE F1 WRCRC BF 46 J(BRDY) C0 BF C1 06 JN(BRDY) C2 C1 C3 F0 CLRCRC C4 46 J(BRDY) C5 C4 C6 F6 CLRWG C7 40 JMP C8 74 C9 00 CA 00 ;and zeros down to so on to FF
Contact information:
Copyright © 2008 Herb Johnson from documents (C) Dwight Elvey
