dll@ut-emx.UUCP (Don Loflin) (07/18/90)
I need some technical info on the trs-80 model 4 P, the portable version of the model 4. I'm interested primarily in the video and keyboard circuitry and software. Can anyone point me to a source? Thanks ============================================================================== Don Loflin dll@emx.utexas.edu ...!uunet!cs.utexas.edu!ut-emx!dll
ee5391aa@hydra.unm.edu (Duke McMullan n5gax) (07/18/90)
In article <34219@ut-emx.UUCP> dll@ut-emx.UUCP (Don Loflin) writes: >I need some technical info on the trs-80 model 4 P, the portable >version of the model 4. I'm interested primarily in the video and >keyboard circuitry and software. Can anyone point me to a source? Yop. Just you go down to your "friendly" Radio Schlock Computer Center, or, heck, just go to the nearest Schlock franchise store. Ask 'em to order item number 26-1080, which is the service manual for the 4p and 4p gate array computers. I _assume_ it's still available. Hope so. May the wind be at your back, d -- "Peace is hell." -- Skyler Duke McMullan n5gax nss13429r phon505-255-4642 ee5391aa@hydra.unm.edu
valsee@qat.UUCP (07/20/90)
> In article <34219@ut-emx.UUCP> dll@ut-emx.UUCP (Don Loflin) writes: > >I need some technical info on the trs-80 model 4 P, the portable > >version of the model 4. I'm interested primarily in the video and > >keyboard circuitry and software. Can anyone point me to a source? > > Yop. Just you go down to your "friendly" Radio Schlock Computer Center, or, > heck, just go to the nearest Schlock franchise store. > > Ask 'em to order item number 26-1080, which is the service manual for the > 4p and 4p gate array computers. > > I _assume_ it's still available. Alternatively, you may contact Tandy National Parts directly via their toll-free customer service line (1-800-442-2425) and order: Part #: MS-2601080 Catalog #: 26-1080 The manual should still be available at this time. (This information is being provided by an individual and should not be construed as being provided by Tandy Corporation/Radio Shack.) Valerie See ....texbell!techsup!qat!valsee valsee@qat.lonestar.ORG
rhealey@ub.d.umn.edu (Rob Healey) (07/22/90)
In article <1990Jul19.212039.10680@techbook.com> fzsitvay@techbook.com (Frank Zsitvay) writes: >>I need some technical info on the trs-80 model 4 P, the portable >>version of the model 4. I'm interested primarily in the video and >>keyboard circuitry and software. Can anyone point me to a source? >Radio shack should still have tech manuals for that machine... > > in model 3 mode, video ram starts at 15360 and goes to 16383. i >don't know if video ram is normally accessable by applications in model 4 >mode. > More precisly: In Model 3 mode: Video is mapped from 0x3C00-0x3FFF Keyboard is mapped 0x3800-0x3BFF The video area is a 64x16 area, one byte is either an ascii character or a graphics character if the 7 bit is set and the ALT character set is not enabled. In model 4 mode use the system calls to access the keyboard and memory, the OS plays bank switching games and you don't want to confuse it. Actually, in Model 3 mode you should also go through the OS, except for high speed graphics and fast full screen updates direct access doesn't really gain you much. The Model 4/4p Technical Reference Manual is Cat. #26-2119 if you can still get one. It has all the hardware dirt on the system and also explains all the OS interfaces and system calls. -Rob