Carlos Murillo <cem14(a)cornell.edu> wrote: I think that makes sense -- it looks like DTR and RTS are under program control (i.e. it's up to software to set the appropriate control register bits). I suspect it depends on what loader ROMs are installed in the computer. There is a loader ROM that supports booting from cartridge tape drives in an attached 264X terminal. In the meantime, I've keyed in the sample program from the manual (at the end of this message). Turning it into executable code and loading that into the 1000E is left as an exercise for the reader, at least 'til I find time to figure out how to do that sort of thing. Others who know are welcome to chime in! Unfortunately, most of the 21xx documentation I have here at home right now is for 2100s, not 21MXs (which are a whole lot closer to 1000s), so I'm just guessing as to what that tells the machine to do, but I expect it's instructions for selecting a given loader ROM (and maybe device) and starting the boot. So...I'll try to keep this in mind for the next foray into storage. What I probably need to look for is the 21MX or 1000 E-Series operating and reference manual, instead of the installation and service manual that I have in front of me. --- cut here --- ASMB,A,B,L,T ORG 100B * ****12966 SAMPLE PROGRAM************************* *THE PROGRAM BEGINS BY CLEARING ALL ADDRESSES OF THE *SPECIAL CHARACTER RAM TO ZEROS.THE 12966 THEN IS *ENABLED TO RECEIVE MODE,1200 BAUD.THE USER ENTERS A *MINIMUM OF 64 CHARACTERS FROM THE TERMINAL KEYBOARD *(HP2640 OR SIMILAR TERMINAL). WHEN BUFFER HALF FULL *(64 CHARS.) IS DETECTED,THE CHARS. ARE TRANSFER FROM *THE FIFO BUFFER OF THE 12966 TO THE CPU. WHEN THIS *TRANSFER IS COMPLETE THE CPU HALTS (HLT 01).THE USER *PRESSES 'PRESET' & 'RUN', THE 12966 GOES INTO THE *TRANSMIT MODE. THE CPU BUFFER (64 CHARS.) IS SENT TO *THE 12966 FIFO BUFFER. WHEN THIS TRANSFER IS COMPLETED *THE 12966 TRANSMITS TO THE TERMINAL UNTIL BUFFER EMPTY *STATUS FLAG SETS. THE CPU NOW HALTS (HLT 02),PRESSING *'RUN' RESETARTS THE PROGRAM. * * A EQU 0 B EQU 1 SCT EQU 12B 12966 IS IN SELECT CODE 12B SAVA BSS 1 SAVB BSS 1 COUNT BSS 1 SIZE DEC 64 64 CHARACTERS BHF OCT 1000 CW3 OCT 030023 CW4R OCT 040011 CW4T OCT 140411 CW5 OCT 050077 CW6 OCT 060000 PAT OCT 777 DAB. DEF DAB CLEAR OCT 060400 ORG 1000B DAB BSS 400 * * ORG 200B START LDA CW4T MASTER RESET,INITIALIZE TRANSMIT OTA SCT LDA CW6 CLEAR OUT SPECIAL CHAR RAM R1 OTA SCT INA CPA CLEAR CHECK IF SPECIAL CHAR RAM IS CLEAR RSS YES IT IS,CONTINUE WITH PROGRAM JMP R1 NO IT ISN'T,CONTINUE CLEARING OVER LDA SIZE SETUP AND INITIALIZE CHAR COUNTER CMA,INA 2'S COMP. STA COUNT LDA CW5 LOAD WORD 5,CLEAR FLAGS OTA SCT LDA CW3 LOAD WORD 3,1 STOP BIT,8 DATA BITS OTA SCT ECHO ON,NO PARITY LDA CW4R LOAD WORD 4,RECEIVE MODE,1200 BAUD OTA SCT CHECK STC SCT,C SET CONTROL 12966 SFS SCT CHECK IF STATUS FLAG SET JMP *-1 NO,NONE IS SET,CONTINUE CLC SCT YES,FLAG HAS SET LIA SCT GET STATUS WORD AND BHF CHECK FOR BUFFER HALF FULL SZA,RSS JMP CHECK BHF NOT SET AS YET LDA CW5 BHF SET,CLEAR STATUS FLAGS OTA SCT LDB DAB. SETUP CPU BUFFER ADDRESS STC SCT,C SET CONTROL 12966 T1 LIA SCT GET A CHARACTER FROM FIFO AND PAT MASK OUT UNWANTED BITS STA B,I STORE CHAR INTO CPU BUFFER INB ISZ COUNT INCREMENT COUNT,COUNT=64? JMP T1 NO,GET NEXT CHARACTER HLT 01 YES,CPU BUFFER IS FULL ***PRESS 'PRESET' AND 'RUN' TO PUT 12966 INTO TRANSMIT *MODE. * NOP LDA CW4T SETUP 12966 TO TRANSMIT @1200 BAUD OTA SCT LDA CW5 CLEAR BUFFERS OTA SCT LDA SIZE SETUP CHAR COUNTER CMA,INA 2'S COMP. STA COUNT LDB DAB. SETUP BUFFER ADDRESS STC SCT,C T2 LDA B,I GET A CHARACTER OTA SCT PUT IT IN THE FIFO BUFFER INB ISZ COUNT INCREMENT COUNT,COUNT=64? JMP T2 NO GET NEXT CHAR!!! LDA CW5 YES,LOAD W TO CLEAR BUFF OTA SCT HALF FULL STC SCT,C SET CONTROL,START TRANSMIT SFS SCT IS BUFFER EMPTY? JMP *-1 NO,CONTINUE SENDING HLT 02 YES, IT IS EMPTY,HALT CPU!! JMP START RESTART 12966 END --- cut here --- -Frank McConnell