shawn@mit-eddie.UUCP (Shawn McKay) (06/18/84)
I have a TRS-80 Model 16A, and am looking for other model 16a users,
as well as people with information leading to the arrest or conviction
of any ports found in connection between the 68000 and the z80. (to
be held for questioning), seriously though, I need mucho info on how
to PROGRAM the model 16, Radio Shack has told me to go jump in a lake
when I ask them for more then a TRSDOS or TRS-XENIX manual for the thing.
As far as I can tell, Tandy has refused to support it to any reasonable
extent, and has refused users (as far as I can tell), the ability to
support it them selfs. I.e. I can't get ANY REAL prints for the thing,
though they sent me out this JOKE they called a service manual.
Has anyone had the same problems with Radio sHACK? Any help, info,
or ideas would be greatly appriciated. All replies directly to me
please, I will be happy to repost to other on request. Thanks in
advance.
Shawn F. Mckay,
Uucp: genrad!mit-eddie!futura!shawn
or mit-eddie!shawn
Arpa: Shawn@Mit-Mcgm@trsvax.UUCP (06/19/84)
#R:mit-eddi:-217300:trsvax:53400037:000:114 trsvax!gm Jun 19 15:06:00 1984 I believe the Model 16B service manual has all the information you need. ...!allegra!convex!ctvax!trsvax!gm
mikey@trsvax.UUCP (06/20/84)
#R:mit-eddi:-217300:trsvax:53400038:000:1043 trsvax!mikey Jun 19 17:28:00 1984 There are no ports common to the Z80 and the 68000 in the model 16. There is a shared 16k window of RAM that is switched in on the Z80 side at address 8000h - BFFFh and is definable on the 68K side. On the Model 16, status is sent by setting flags in memory in the window. All this information is in the copy of the Model 16 service manual that was published, (at least in my copy) but if you were looking for a port, it is probably easy to overlook. For communication, you must first switch out the bank of memory normally at 8000-FFFF hex which is controlled at port FF and then use the memory control port on the 68K card to switch in a 16k window of the 68K memory. Since this window is definable as to its location in the 68K memory, this is also how you load your original 68K startup program. If you're going to muck around, I suggest you do it from TRSDOS 2.0x, as 2.0 has no idea of the existance of the 68K or the extra RAM. TRSDOS 4.x will try use the 68K ram to put some I/O buffers and drivers there. mikey at trsvax