tswift@well.sf.ca.us (Theodore John Swift) (02/22/91)
Sorry to post this to the whole net. I lost James' login. But others of you may find this interesting. - > If you find out how to do what you need, please let me know. And you! > I've found out how to interface to the printer parallel port by > trial and error; no documentation. I've got two bits in and eight > bits out. As for documentation, I think the plain user's manual talks about the printer some, but if not, there are two other sources I'd suggest (quoting from a letter to another net-person): ---- He asked: > Are there any trs-80 model 100 users groups around out there? I just > acquired one recently and I would like to find some info. on programming > the thing in assembly and especially doing graphics from assembly. I replied: There's a book called _Inside The (TRS-80) Model 100_ by Carl Oppedahl, Copyright 1985 by Weber Systems, published by Weber Systems, Inc., 8437 Mayfield Road, Chesterland, Ohio 44026. ISBN 0-938862-31-6. $19.95 I got my copy about six months ago at Computer Literacy Bookstore in Sunnyvale, CA (408) 730-9955 (if you have trouble locating it nearby). It contains 18 chapters, and describes the hardware in detail, and goes into some detail about programming in assembly and advanced BASIC. Chapter heads: 1 Introduction to the Model 100; 2 Assembly Programming; 3 Advanced BASIC; 4 Borrowing from Z80 Experience; 5 Understanding the Hardware of the Model 100; 6 The Keyboard; 7 UART operation and the RS-232 Interface; 8 The Telephone Modem; 9 Piezoelectric Beeper; 10 The Printer Interface; 11 Clock/Calendar; 12 Cassette I/O; 13 The LCD Screen; 14 The Bar Code Reader; 15 Interrupts; 16 The Power Supply; 17 Expansions; 18 The Remainder of ROM; Apdx A, Nonprintable Characters and Assignments; Apdx B, ROM Map; Apdx C, 8080, 8085, Z80 Opcodes; Apdx D, Bibliography. ----- Another source you might consider is the Rat Shack Service Manual, cat no. 26-3801/3802. It's got a wealth of information about schematics, theory of operation, graphics character codes, etc. > I've got two bits in and eight bits out. Well, that's pretty good for not having any documentation, but I think your shy one output: _Inside the Model 100_ says (and the RS Service Manual confirms) that the printer port conforms to the Centronics standard. Table 10.1 of _ITM100_ gives the lines: Centronics M100 Function Source Pin Pin 1 1 Strobe-not M100 2 3 DATA 0 M100 3 5 DATA 1 M100 4 7 DATA 2 M100 5 9 DATA 3 M100 6 11 DATA 4 M100 7 13 DATA 5 M100 8 15 DATA 6 M100 9 17 DATA 7 M100 10 19 ignored by M100 11 21 BUSY printer 12 23 ignored by M100 13 25 BUSY-not printer 15-18 NC 19 2 Ground | (evens) | 30 24 Ground 31 26 ignored by M100 32-36 NC "Many printers announce that they are out of paper by asserting a high signal at Centronics pin 12, which goes to M100 pin 23, but this signal goes nowhere within the M100". > What I really need is an interrupt input pin. Is there one? > James Yes, there is one: INTR, pin 17, is an input. INTA, pin 24, is an output according to Table 17.2 of _ITM100_. It also cautions that "This is not a technique for the idle experimenter" :-). The Service Manual writes that "INTR, interrupt request, is a general purpose interrupt. It is sampled only during the next to the last clock cycle of an instruction and during Hold and Halt states. If it is active, the Program Counter (PC) will be inhibited from incrementing and an INTA-not will be issued. During this cycle a Restart or Call instruction can be inserted to jump to the interrupt service routine. The INTR is enabled and disabled by software. It is disabled by Reset and immediately after an interrupt is accepted. INTA-not, interrupt acknowledge, is used instead of (and has the same timing as) RD-not during the Instruction cycle after an INTR is accepted". These lines go directly to the 8085 processor. Good luck in your efforts. If you have any tips, I'd appreciate hearing from you. I'll write as I discover new stuff. -- ---------------------- Ted Swift tswift@well.sf.ca.us "You bally well are informed, Jeeves! Do you know everything?" "I don't know, sir" ~P.G. Wodehouse
fiori@ziggy.Quantum.Leap.COM (Wayne Fiori) (02/26/91)
I'm relatively new to the world of laptops and I have recently considered getting a used (read cheap) laptop to use as an intellegent portable terminal. The first portable that came to mind was the trs model 100. Could anyone tell me what a good price would be for a used one? Even better, is Radio Shack still carrying these? Thanks...
PZ2@psuvm.psu.edu (David L. Phillips) (02/27/91)
In article <12796@darkstar.ucsc.edu>, fiori@ziggy.Quantum.Leap.COM (Wayne Fiori) says: >Even better, is Radio Shack >still carrying these? > Last I saw, they were carrying the Model 102, which is the same thing only smaller. Price was in the $400-$500 range, but they have sales from time to time.
cortez@ux1.cso.uiuc.edu (Jeff Cortez) (02/27/91)
PZ2@psuvm.psu.edu (David L. Phillips) writes: >In article <12796@darkstar.ucsc.edu>, fiori@ziggy.Quantum.Leap.COM (Wayne Fiori) >says: >>Even better, is Radio Shack >>still carrying these? >> >Last I saw, they were carrying the Model 102, which is the same thing only >smaller. Price was in the $400-$500 range, but they have sales from time to >time. Yeah I think the current list price is $499. If you can find it used I would suggest you grab it up. A normal used price would be around $100. Before you buy it I would seriously suggest though that you define in your mind exactly what you want to do with it. It is nifty computer for those who are on the go and who need to write notes, memos, even papers, but it is not the computer for you if you have in mind spreadsheets, high-speed communications, or games. It only has 32k and it runs at about 2MHz and it is completely incompatible with DOS machines. If have any specific questions about what it can or can't do write me and I will try to help. Jeff Cortez tandy@uiuc.edu Maintainer of the Tandy 100 Archives
silvert@cs.dal.ca (Bill Silvert) (02/27/91)
In article <1991Feb26.205640.27318@ux1.cso.uiuc.edu> cortez@ux1.cso.uiuc.edu (Jeff Cortez) writes: >PZ2@psuvm.psu.edu (David L. Phillips) writes: > >>In article <12796@darkstar.ucsc.edu>, fiori@ziggy.Quantum.Leap.COM (Wayne Fiori) >>says: >>>Even better, is Radio Shack >>>still carrying these? >Yeah I think the current list price is $499. If you can find it used I >would suggest you grab it up. A normal used price would be around $100. >Before you buy it I would seriously suggest though that you define >in your mind exactly what you want to do with it. It is nifty computer >for those who are on the go and who need to write notes, memos, even >papers, but it is not the computer for you if you have in mind spreadsheets, >high-speed communications, or games. It only has 32k and it runs at >about 2MHz and it is completely incompatible with DOS machines. It should be noted that there are several ROMs that plug into the Model 100 that handle spreadsheets (notably Lucid), and although the builtin modem only runs at 300 baud, the software supports rates up to 19200 baud (I think -- I've only run at 9600). There is also the Model 200, almost the same size but with a clamshell case that gives you 16 lines instead of the 8 on the 100 or 102. It comes with a spreadsheet in ROM. -- William Silvert, Habitat Ecology Division, Bedford Inst. of Oceanography P. O. Box 1006, Dartmouth, Nova Scotia, CANADA B2Y 4A2. Tel. (902)426-1577 UUCP=..!{uunet|watmath}!dalcs!biomel!bill BITNET=bill%biomel%dalcs@dalac InterNet=bill%biomel@cs.dal.ca