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Forum: General Discussion
 Topic: SmallZ80
Re: SmallZ80 [message #5521 is a reply to message #5305] Thu, 15 November 2018 10:28
Wayne W is currently offline  Wayne W
Messages: 273
Registered: October 2015
Location: Fountain Valley, Californ...
Senior Member
I know I mentioned this system here previously, but thought
I would provide a little more detail having recently built
a pre-production version of the system.

Terry Gulczynski is getting ready to
produce a run of these kits, so if you are interested, you
should contact him. His email address is
terryg@stack180.com

The SmallZ80 is a compact and full-featured Z80 system
with excellent performance and reliability. It is comprised
of a relatively small main CPU board (~5"x6.5") and an
optional expansion board (~3"x4"). Construction is straightforward
with all through-hole components (there are a couple of small SOIC
chips on the expansion board that come pre-soldered).

The main CPU board features:

  • Z80 CPU (dual-speed, dynamically switchable)
  • 32K EEPROM
  • 544K SRAM (32K fixed & 512K banked)
  • Real-time Clock w/ battery
  • IDE Interface (supports primary and slave devices)
  • 2 Serial Ports
  • LED connections for power, drive activity, and disgnostics (3)


The optional expansion board adds the following features:

  • Dual drive floppy interface
  • Two serial ports, -or-
  • Ethernet LAN interface for terminal and printer


Completing the system requires only adding a +5V power source,
floppy drive(s) (optional), and a case.

A very complete software implementation is included. The ROM
firmware manages booting and provides system configuration,
testing, and monitor functionality.

A CF Card image is provided which implements an enhanced
version of ZCPR 3.3 and a very complete set of system tools.
I had no trouble running a variety of standard CP/M applications
such as WordStar.

Performance is the best I have seen for a Z80-based system.
The system runs reliably at the maximum Z80 CPU clock speed
of 20MHz. There are no added wait states for
I/O or memory. Additionally, the serial ports are rated for
operation up to 230,400 baud, but I am running mine reliably
at 460,800 baud (close to 0.5mbps).

The IDE interface on the system is ideally suited for
use with CompactFlash cards. A small CF adapter is installed
that allows 1 or 2 CompactFlash cards to be used. Access
speeds are very fast.

The ethernet interface on the expansion board is probably my
favorite feature. After powering on the system, you can
simply connect to it via any Telnet-type terminal software.
The ethernet interface on the board runs at 921,600 baud
and provides extremely fast terminal speeds. The same
ethernet interface can also be used to print to a LAN
connected printer.

If you like the retro feel of floppy drives, they are
easily connected via the expansion board. You can use
a standard PC-type floppy cable with a twist to install
up to 2 3.5" drives.

Complete documentation is included and thoroughly covers
assembly, operation, and technical details of the system
including schematics. The documentation is freely
available on Terry's website at www.stack180.com.

Overall, the SmallZ80 provides a system with excellent performance,
reliability, and functionality for a great price and small
package. The system has a very professional feel to it for
a kit of this type and cost.

Terry has posted pricing for both boards on his website.
All parts are included, but not a case or shipping. Definitely
what I would call "hobbyist friendly" pricing.

-Wayne

index.php?t=getfile&id=1136&private=0
index.php?t=getfile&id=1137&private=0
index.php?t=getfile&id=1138&private=0

[Updated on: Thu, 15 November 2018 10:47]

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 Topic: Interested in a Z280 SBC
Re: Interested in a Z280 SBC [message #5519 is a reply to message #5516] Thu, 15 November 2018 04:27
hperaza is currently offline  hperaza
Messages: 50
Registered: March 2017
Member
agn453 wrote on Wed, 14 November 2018 12:26
Also, I've hit the 512 directory entries limit on the CompactFlash 8MB drives a few times (particularly with timestamps enabled). I'm considering increasing it to 1024 for the optional drives E:..H: that can be configured in my BIOS.

I'd go directly for 4096 directory entries - once you start copying files, assembling and/or compiling applications you will hit the 1024-entry limit very quickly (at least that was my experience with a 10MB GIDE partition on the P112). Remember that in CP/M # of dir entries <> max # of files, as large files (e.g. assembly listings) take several directory entries. Also, in CP/M 3 1/4 of the entries are used by the timestamps (when enabled).
Re: Interested in a Z280 SBC [message #5520 is a reply to message #5519] Thu, 15 November 2018 10:07
geowar1 is currently offline  geowar1
Messages: 35
Registered: October 2018
Member
The limit I hit is the one in my brain... More than 512 files in one directory is more than I can mentally keep track of... especially when file names are limited to the 8.3 and no mixed case. I find user areas less that useful (even with any/all of the z80 dos extensions) because there's always something I need that's I can't access from the user area where I'm working.
Re: 8080 to Z80 translation [message #5522 is a reply to message #5515] Thu, 15 November 2018 11:19
geowar1 is currently offline  geowar1
Messages: 35
Registered: October 2018
Member
There are two here: http://www.hytherion.com/beattidp/comput/z80cpm.htm
One is an awk script that you can run anywhere... you can run awk scripts... [duh!] ;-)
The other (<ZTRANS.COM>) is (CP/M Z80) native app.

I'd be interested in how they compare with the one that you're using... I suspect they have the same issues; I find I have to double check all / manually switch "M" to '(HL)' sometimes... and re-do any 8080/Z80 macros "JRNZ", etc.

I've been tempted to disassemble ZTRANS.COM to make it output lower case... but I've been xmodem'ng up to host (macOS) and then using bbedit to convert to lower case and then xmodem'ng back down to the target (z280rc) machine.

Re: 8080 to Z80 translation [message #5523 is a reply to message #5522] Thu, 15 November 2018 11:29
lowen is currently offline  lowen
Messages: 179
Registered: August 2016
Location: Western NC USA
Senior Member
geowar1 wrote on Thu, 15 November 2018 14:19
...
I've been tempted to disassemble ZTRANS.COM to make it output lower case... but I've been xmodem'ng up to host (macOS) and then using bbedit to convert to lower case and then xmodem'ng back down to the target (z280rc) machine.



I have to admit that I for one have difficulty reading lowercase assembler code; I write and wrote in all upper case for assembler for so long that lowercase assembler just feels Wrong. Smile


--
Bughlt: Sckmud
Shut her down Scotty, she's sucking mud again!
Re: 8080 to Z80 translation [message #5524 is a reply to message #5523] Thu, 15 November 2018 11:50
snhirsch_gmail.com is currently offline  snhirsch_gmail.com
Messages: 61
Registered: May 2017
Member
Here's the sources for an Intel to Zilog translator in C. I hacked it a bit to get it working on Linux.
Re: Interested in a Z280 SBC [message #5525 is a reply to message #5520] Thu, 15 November 2018 12:40
etchedpixels is currently offline  etchedpixels
Messages: 150
Registered: October 2015
Senior Member
With CP/M 3 as with MP/M you can mark files as system files in which case they can be run/read regardless of user area and you can list them with DIRS rather than DIR

It's one of the little things that makes CP/M 3 so much more pleasant to use.
Re: Interested in a Z280 SBC [message #5526 is a reply to message #5519] Thu, 15 November 2018 13:45
agn453 is currently offline  agn453
Messages: 33
Registered: June 2018
Location: Newcastle, NSW, Australia
Member
hperaza wrote on Thu, 15 November 2018 23:27

I'd go directly for 4096 directory entries - once you start copying files, assembling and/or compiling applications you will hit the 1024-entry limit very quickly
..snip..


Hector,

Having thought about this again I've elected to use 2048 directory entries. Going higher would mean I'd need to use a block size of 8192 (BLS) and I'd rather stick with 4096 so the small files aren't chewing up a bigger allocation.

Yet another aside - I noticed reference to RSX180 in your ZSM4 distribution. A DuckDuckGo search seems to only have a reference to your P112 site for a disk image (for the P112). Is this the PDP-11 RSX system migrated to a Z180? Over 40 years ago (around the time I was getting into microcomputers) I spent too much time after work hours tinkering on RSX-11M. Is the source code available? If you'd rather respond privately - use Tony Nicholson at computer dot org to reach me.

Tony



--
Tony Nicholson
Re: 8080 to Z80 translation [message #5527 is a reply to message #5524] Thu, 15 November 2018 14:28
agn453 is currently offline  agn453
Messages: 33
Registered: June 2018
Location: Newcastle, NSW, Australia
Member
My quick-and-dirty TurboPascal program to lowercase assembly language source (and leave comments alone) is attached. The only thing to watch for
is for single quotes in text strings - like DEFB "Can't open file" - or EX AF AF' - which may cause comments to be lowercased too.

Tony
  • Attachment: LC.PAS
    (Size: 1.26KB, Downloaded 1 time)


--
Tony Nicholson
Re: Interested in a Z280 SBC [message #5528 is a reply to message #5525] Thu, 15 November 2018 15:21
geowar1 is currently offline  geowar1
Messages: 35
Registered: October 2018
Member
yeah, that works... unfortunately it doesn't help with non-COM (or SUB) files... for example all those <WS*.OVR> files... You can tell WS4 to always get them from whatever drive they're on... but not which user area.
Weirdly HELP.com can find HELP.HLP (and *.HLP)... but a lot of other programs can't find their files unless they're in the same user area.
Re: Interested in a Z280 SBC [message #5529 is a reply to message #5528] Thu, 15 November 2018 15:36
agn453 is currently offline  agn453
Messages: 33
Registered: June 2018
Location: Newcastle, NSW, Australia
Member
geowar1 wrote on Fri, 16 November 2018 10:21
yeah, that works... unfortunately it doesn't help with non-COM (or SUB) files... for example all those <WS*.OVR> files... You can tell WS4 to always get them from whatever drive they're on... but not which user area.
Weirdly HELP.com can find HELP.HLP (and *.HLP)... but a lot of other programs can't find their files unless they're in the same user area.


Try the ZCPM3 BDOS.

I use this feature when working in different user areas - for example, the majority of my .COM and .SUB files - including Wordstar 3.30g and it's overlays reside on disk A in user 0 - each of them marked with the SYS and RO attribute. They can be found using the search path (set-up with SETDEF in the PROFILE.SUB on boot) or (for those that don't use a search path) in user 0 of the current drive. WordStar has a WINSTALL option to specify which drive the overlays are on.

Tony


--
Tony Nicholson
Re: Interested in a Z280 SBC [message #5530 is a reply to message #5518] Thu, 15 November 2018 17:10
geowar1 is currently offline  geowar1
Messages: 35
Registered: October 2018
Member
I wasn't aware that DU had a CP/M Plus version... not to say you couldn't boot into CP/M 2.2 to do what you did...
OTOH I did find the source to ZAP modified to work on CP/M Plus... except that it had a bug where he didn't handle more than 127 sectors per track (and z280rz uses 256 spt).
If you're interested I can post it (w/sources).

Next I want to write a "mount" command that can change the system track offsets on any but the boot drive so I can remap any logical drive (except A:) to any (64 track) partition on the CF card.

Note: while playing with your BIOS (and rebuilding, and rebuilding, and...Wink I decided to write a "IFNT" tool. Sets the CP/M Plus BDOS FUNCTION 108: GET/SET PROGRAM RETURN CODE appropriately based on relative file update time(stamps).
So your BANKBIOS.SUB script can do things like this:

ifnt scb.mac scb.rel
:ZSM4 SCB,SCB=SCB/s8/u

ifnt bioskrnl.mac bioskrnl.rel
:ZSM4 BIOSKRNL,BIOSKRNL=BIOSKRNL/s8/u

ifnt idehd.mac idehd.rel
:ZSM4 IDEHD,IDEHD=IDEHD/s8/u

ifnt ramdisk.mac ramdisk.rel
:ZSM4 RAMDISK,RAMDISK=RAMDISK/s8/u

ifnt clock.mac clock.rel
:ZSM4 CLOCK,CLOCK=CLOCK/s8/u

ifnt chario.mac chario.rel
:ZSM4 CHARIO,CHARIO=CHARIO/s8/u

ifnt biosdbg.mac biosdbg.rel
:ZSM4 BIOSDBG,BIOSDBG=BIOSDBG/s8/u

ifnt BIOSKRNL.rel,BIOSDBG.rel,CHARIO.rel,CLOCK.rel,SCB.rel,RAMDISK.rel,IDEHD.rel BNKBIOS3.spr
:LINK BNKBIOS3[B]=BIOSKRNL,BIOSDBG,CHARIO,CLOCK,SCB,RAMDISK,IDEHD


Works pretty well... (except that CP/M Plus time stamps only have one minute resolution... so sometimes something that's "newer" actually has the same date...]

Why didn't they use "seconds since 1977" instead of "days since 1977 plus hh:mm"? (no 32-bit divide?Wink That would have lasted 136 years (or 116 years longer than CP/M did). As-is the file stamps are good for ≈179 years... but no seconds. Sad
Re: Interested in a Z280 SBC [message #5531 is a reply to message #5529] Thu, 15 November 2018 17:13
geowar1 is currently offline  geowar1
Messages: 35
Registered: October 2018
Member
Yeah, that's what I did (except everything on drive B:).
I used NZCOM right up until Joe Wright retired and moved back east (I helped him pack up)... but my zrdos foo has fled... :(

Will the ZCPM3 BDOS give me a command history longer than one entry?
Re: 8080 to Z80 translation [message #5532 is a reply to message #5523] Thu, 15 November 2018 17:16
geowar1 is currently offline  geowar1
Messages: 35
Registered: October 2018
Member
Even back when I was doing more assembly programming (30+ years ago!Wink I exclusively used lower case... I've never liked how Micro$oft & Intel like to YELL (UPPERCASE) everything.
Still beats toggling it in via the front panel (like on the PDP-11)... ;-)
Re: Interested in a Z280 SBC [message #5533 is a reply to message #5531] Thu, 15 November 2018 17:27
agn453 is currently offline  agn453
Messages: 33
Registered: June 2018
Location: Newcastle, NSW, Australia
Member
geowar1 wrote on Fri, 16 November 2018 12:13
Will the ZCPM3 BDOS give me a command history longer than one entry?


Yep - Wordstar like cursor keys. CTRL-X and CTRL-E for command history up/down... CTRL-Y (delete line) replaces the CP/M CTRL-U.. CTRL-S CTRL-D cursor left and right etc.

Tony


--
Tony Nicholson
Re: Interested in a Z280 SBC [message #5534 is a reply to message #5533] Thu, 15 November 2018 17:59
geowar1 is currently offline  geowar1
Messages: 35
Registered: October 2018
Member
Know of any documentation anywhere? Only thing I can find via google is some DDJ articles and < http://elitebbs.dynu.net/commodore/commodore/Commodore%20Fil e%20Areas/8-cpm/zcpm3.html>... lots of verbiage... no actual information.

Re: 8080 to Z80 translation [message #5535 is a reply to message #5527] Thu, 15 November 2018 18:01
geowar1 is currently offline  geowar1
Messages: 35
Registered: October 2018
Member
BTW: It annoys me that you can't use "ex hl,de" (or I guess "ex af',af" ether).
Re: Interested in a Z280 SBC [message #5536 is a reply to message #5534] Thu, 15 November 2018 18:33
agn453 is currently offline  agn453
Messages: 33
Registered: June 2018
Location: Newcastle, NSW, Australia
Member
For a summary of Simeon Cran's ZPM3 BDOS features, please see the zpm3s.arc file I attached to my recent message.

It contains the disassembled source code (that Hector graciously fixed ZSM4 so it would build without throwing errors due to long symbols).

In it you will also find a ZPM3.TXT and a ZPM3FIX.TXT file that will give some help.

This copy came from Tesseract RCPM+ Volume 93 and was updated on 24-Feb-2015 by Jon Saxton. Jon changed the key mapping and command history to be "more intuitive" - so be sure to read the "fix" file.

Tony


--
Tony Nicholson



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