Re: Z180 (was: Captain Video)
TI-86 is a Z80 with 128mb of memory, so likely one of the processors you guys are talking about, too. Display on them is essentially the same as the TRS-80 computers, except maybe for graphics. There were ways to load progams onto it and run them, but by the time I found out about them my TI-86 was having display problems. It was the last TI I bought for myself as they just abandoned it. While mine was still pretty new! The rats. Of course I'n not the only one TI did that to.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects.
LAZARUS LONG (Robert A. Heinlein)
On Tuesday, August 4, 2020, 06:42:32 PM CDT, Lee Hart <leeahart@...> wrote:
ajparent1/kb1gmx wrote:
> FYI 64180 and Z180 are to most still a z80 and programs at the
> application level (CP/M) the same.
Yes. Besides the P112, there have in fact been many follow-in
enhancements to the Z80 family. The current TI-84 calculators still use
them today.
> Z180/64180 were z80s aka 8-bitters. 8088 and z8000 and 68000 were bigger
> word size and minimally 16-bit.
Sort of... 8- vs. 16-bit is a blurry line. It's hard to call the 8088 a
16-bit CPU, except in marketing. At the same clock speed, the Z80 easily
out-performed it. The Z180 was even faster, and had a bigger address
space as well.
> 8088 was Totally program (binary) incompatable. But it was a thing.
Yep. Marketing over engineering.
Lee
--
A designer knows he has achieved perfection not when there is
nothing left to add, but when there is nothing left to take away.
? ? ? ? -- Antoine de Saint Exupery
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
|
Z180 (was: Captain Video)
ajparent1/kb1gmx wrote: FYI 64180 and Z180 are to most still a z80 and programs at the
application level (CP/M) the same. Yes. Besides the P112, there have in fact been many follow-in enhancements to the Z80 family. The current TI-84 calculators still use them today. Z180/64180 were z80s aka 8-bitters. 8088 and z8000 and 68000 were bigger
word size and minimally 16-bit. Sort of... 8- vs. 16-bit is a blurry line. It's hard to call the 8088 a 16-bit CPU, except in marketing. At the same clock speed, the Z80 easily out-performed it. The Z180 was even faster, and had a bigger address space as well. 8088 was Totally program (binary) incompatable. But it was a thing. Yep. Marketing over engineering. Lee -- A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away. -- Antoine de Saint Exupery -- Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
|
>>>I will say the Z180 is a very interesting chip. I looked at it a lot as the Hitachi HD64180, which was available in a 64-pin DIP. But for some reason, it never got much "traction" in the market, so there wasn't much point in making a kit version of it. I'm glad to see someone has.<<<
There was the P112 and its follow on.? IT was popular but the date was 1980 and 8088 was?
showing its face finally (it had ben around for a while but no takers).
.
FYI 64180 and Z180 are to most still a z80 and programs at the application level (CP/M) the same.
What the big deal Z180/64180 were z80s aka 8bitters..? 8088 and z8000,and 68000 were
bigger word size and minimally 16bit.? ?When everyone decided 16 it was it, the market
shifted fast and by the summer of 81 (just pre PC) it was already a 16 bit world.? Not to
say 8bitter were not in use but they were already hitting the memory wall.
TWhe sallwarts went to Z180/64180 as it was faster, offered the potential for
larger memory space (512k) and CP/M3, Zrdos and a few other cp/m compatables
could support that space.? The apps were still Z80 but way faster.??
8088 was nearly as easy to build up as the 8085.? Totally program (binary) incompatable.
But it was a thing.
Allison
|
64180 was availabe in that large pin dense dense dip or flatpack [J lead TQFP]
as is the Z180 and they are both about the same.? I have both and save for
clock speed same thing.? ITs biggest features are built in dual uart (dart similar),
a bit serial somewhat like I2C, timers and DMAC.? There are screamingly fast
versions to be found, I have a handful at 10mhz and one that is spec'ed for 20.
I also have SB180 that used the 64pin dip with the SCSI interface and the?
BCC180 (at 18.432mhz) using the TQFP as well as a few HB designs.
What makes the Z180/64180 less popular is programming the MMU is a
real pain.? The result of any programming is still only 64k addressable
space scattered in the 512K (64pin) or 1MB (TQFP) space.? That and
not everyone likes the onboard peripherals.
There is the much harder to find Z280, takes a z180 and adds 16bit wide (startup
configurable) bus for speed and extended but upward compatible instruction set
with indirect addressing modes and 24bit addressing via I&D spaces plus a real
MMU.? That part makes it easy to have 8mb ram and 8mb rom.? You need mask
level parts higher than H for fewest bugs.? Performance for the Jrev at 12mhz?
can beat a 8086 up to 16mhz.
However for just plain fun the base Z80 at 4-10mhz is a good pick for simple
systems.
Allison
|
I'm hoping there will be a way to put video on it, one of these days. I'm pretty much starting from scratch, as far as legacy computers go. May have to rob the chips from this one to go on a different board. Been a long time since I did any electronics. I may have to go back to school for that, too.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects.
LAZARUS LONG (Robert A. Heinlein)
On Sunday, August 2, 2020, 03:46:07 PM CDT, Lee Hart <leeahart@...> wrote:
Bill in OKC too via groups.io wrote:
> Pretty sure I said yes on every option, except color of the case, where
> I selected blue. So I won't worry about it until the thing arrives.
This is a pretty interesting little micro. I'm interested to hear how it
turns out! But it's off-topic for this thread, as it doesn't have video
at all. You may want to continue discussions on a new thread?
I will say the Z180 is a very interesting chip. I looked at it a lot as
the Hitachi HD64180, which was available in a 64-pin DIP. But for some
reason, it never got much "traction" in the market, so there wasn't much
point in making a kit version of it. I'm glad to see someone has.
Lee Hart
--
A designer knows he has achieved perfection not when there is
nothing left to add, but when there is nothing left to take away.
? ? ? ? -- Antoine de Saint Exupery
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
|
Bill in OKC too via groups.io wrote: Pretty sure I said yes on every option, except color of the case, where
I selected blue. So I won't worry about it until the thing arrives. This is a pretty interesting little micro. I'm interested to hear how it turns out! But it's off-topic for this thread, as it doesn't have video at all. You may want to continue discussions on a new thread? I will say the Z180 is a very interesting chip. I looked at it a lot as the Hitachi HD64180, which was available in a 64-pin DIP. But for some reason, it never got much "traction" in the market, so there wasn't much point in making a kit version of it. I'm glad to see someone has. Lee Hart -- A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away. -- Antoine de Saint Exupery -- Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
|
Just got the confirmation email, did order the usb cable and ftdi adapter. Didn't remember that, but did know I left a yes anywhere it would take one. They're quote 3-5 weeks shipping time. I'm gonna need to stay busy. ;)? I may just have to order a powered USB hub. I've wanted one for several years, this could be a good excuse.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects.
LAZARUS LONG (Robert A. Heinlein)
On Sunday, August 2, 2020, 12:25:20 PM CDT, Mark Moulding <mark@...> wrote:
The unit is a bit touchy about power.? I couldn't run it of the USB hub under my monitor, because the voltage under load was too low (4.70).? Plugged directly into the computer, it works fine.
~~
Mark Moulding
|
The unit is a bit touchy about power.? I couldn't run it of the USB hub under my monitor, because the voltage under load was too low (4.70).? Plugged directly into the computer, it works fine.
~~
Mark Moulding
|
Pretty sure I said yes on every option, except color of the case, where I selected blue. So I won't worry about it until the thing arrives. Though I was thinking have both in place, and use one for power? and the other for signal. Just in case it has trouble with the current draw. Instructions mentioned that could be a problem. Or I suppose I could cheat and put a connector on it for a wall wart. I've got a couple of those laying around here that put out a regulated 5VDC at half an amp. That would be plenty of power to run it. Somewhere here I have a USB-to parallel printer cable, but I don't think any of my remaining printers have the parallel interface. USB or Ethernet/WiFi these days. I guess I'll have to see if ftdi to USB will run a USB printer. Finding a Wordstar printer driver for my Epson Workforce WF-7620 might be interesting. ;)
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects.
LAZARUS LONG (Robert A. Heinlein)
On Sunday, August 2, 2020, 09:51:43 AM CDT, Mark Moulding <mark@...> wrote:
Bill, if you selected "Yes, Please" to the USB-Serial adapter option when you bought the full kit, it will come with one; that's what I'm using, and it works perfectly.,? That said, it looks pretty generic - it's just one of the board-level devices with a mini-USB socket on one end and a six-pin connector on the other, so any of the Arduino-type devices ought to work OK, too.? The ones you found on Amazon look identical to the one that came with the kit.
You only need one for the console to run CP/M effectively.? I've been considering building a TTL-RS-232 level shifter for the second port, and using it as a printer port (it's currently configured that way in the CP/M BIOS).
~~
Mark Moulding
|
Bill, if you selected "Yes, Please" to the USB-Serial adapter option when you bought the full kit, it will come with one; that's what I'm using, and it works perfectly.,? That said, it looks pretty generic - it's just one of the board-level devices with a mini-USB socket on one end and a six-pin connector on the other, so any of the Arduino-type devices ought to work OK, too.? The ones you found on Amazon look identical to the one that came with the kit.
You only need one for the console to run CP/M effectively.? I've been considering building a TTL-RS-232 level shifter for the second port, and using it as a printer port (it's currently configured that way in the CP/M BIOS).
~~
Mark Moulding
|
I've copied everything I could find on the internet, but I'll happily take anything you want to send my way, too. I do have a question for you on hardware, though. Can you recommend an ftdi card or cards so I can talk to the thing when it gets here.? I've got these sitting in my amazon cart, with some 4" jumper leads for hookup, but not sure this is the best option. Also don't know if I'll need two, or if just one will do.?
The Tindie site warns of possible long delays in shipping due to Covid-19, so no telling how long it will take for the hardware kit to get here. I got a book I bought from the UK in less than a week, but they seem to think it could be months, too.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects.
LAZARUS LONG (Robert A. Heinlein)
On Saturday, August 1, 2020, 09:32:06 PM CDT, Mark Moulding <mark@...> wrote:
Bill, I saved almost all of my CP/M stuff in files in my master "everything I've ever done" hard drive archive, so if there's anything you need (WordStar in file form, rather than disks), let me know.
I found a copy of Adventure (Colossal Cave) for CP/M, and copied that all into User space 1.? That's always good for a ten-minute break, too...
~~
Mark Moulding
|
Bill, I saved almost all of my CP/M stuff in files in my master "everything I've ever done" hard drive archive, so if there's anything you need (WordStar in file form, rather than disks), let me know.
I found a copy of Adventure (Colossal Cave) for CP/M, and copied that all into User space 1.? That's always good for a ten-minute break, too...
~~
Mark Moulding
|
Alright, Mark & Alison. This is your fault! I ordered one. I am absolutely not responsible for my own actions!?
I have to wonder if I'll have any clue how to run the silly thing. Though I did find my copy of Zaks' Introduction to Microprocessors the other day. Maybe I won't have to cry like a baby and beg for help. No bets. I think I still have my Wordstar 3 disks...?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects.
LAZARUS LONG (Robert A. Heinlein)
On Saturday, August 1, 2020, 07:40:42 PM CDT, Mark Moulding <mark@...> wrote:
Alison, I picked up a few weeks ago.? It went together in about an hour, and is very close to what you described.? It uses a Z-180 (Z*) code compatible, plus two serial ports (and some other stuff) on-chip.? It comes with a micro-SD pre-loaded with several versions of CP/M and a few others as well (Z-System, Forth, Basic).? Each "Hard drive" on the SD card is broken into 16 "Slices", each of which is the 8 MB maximum size for CP/M.? The whole thing is only a little bigger than a deck of cards, and costs about $75.? Looking at the listing on Tindie, it appears that it may not be available much longer...
It's really fun to use - I leave it plugged into my main computer (it can be powered from the USB-serial adapter).? Then when I'm working on something else and need a break, I just fire up my H-19 emulator, and away I go!? I've loaded WordStar (my favorite editor of that era), as well as Turbo Pascal (which achieved for me what P-System did for you), so I'm back in 1981.
~~
Mark Moulding
|
Alison, I picked up a few weeks ago.? It went together in about an hour, and is very close to what you described.? It uses a Z-180 (Z*) code compatible, plus two serial ports (and some other stuff) on-chip.? It comes with a micro-SD pre-loaded with several versions of CP/M and a few others as well (Z-System, Forth, Basic).? Each "Hard drive" on the SD card is broken into 16 "Slices", each of which is the 8 MB maximum size for CP/M.? The whole thing is only a little bigger than a deck of cards, and costs about $75.? Looking at the listing on Tindie, it appears that it may not be available much longer...
It's really fun to use - I leave it plugged into my main computer (it can be powered from the USB-serial adapter).? Then when I'm working on something else and need a break, I just fire up my H-19 emulator, and away I go!? I've loaded WordStar (my favorite editor of that era), as well as Turbo Pascal (which achieved for me what P-System did for you), so I'm back in 1981.
~~
Mark Moulding
|
>>>Early on, CP/M computers with primiive software and floppy disks really slowed software development. But that's all I had; I didn't know any better. It sure as heck beat a CPU manufacturer's development system with paper tape and a teletype! So I was in heaven. :-)<<<
I hear an Amen!? ?
For any system running off TTY and slow storge and minimal tools was a serious
handicap.
PRE CP/M development with SYS-8 (or the PT equivilent) was slow and awkward.
Same for any of the other CPUs.? The 1802 has the potential but most systems are?
low end so paper tape (cassette tape) wis about it and the tools are weak too.? I can?
say the exact same for 6800, 6502, Signetics 2650,8085, Ti9900, PDP-8, and many?
others.
FYI I believe the first break though was UCSD Pascal Psystem, in my case on
Northstar Horizon.? IT got me several things a language faster than interpreted
BASIC and better structured, a real IDE with a solid P-compiler and a real
screen editor.? In 1979 that was a big deal!? ?CP/M I'd been running since V1.3
and all of the neet stuff had to be transferred from 8"SSSD to NS* hard sector
5.25. With S100 it was easy to add a fairly low cost controller card and scrounge
up an 8" SC800 (loud and heavy) as a added disk and transfer media.? ?After that
C compilers started to appear (BDS-C was one of the good ones) and decent
configurable full screen editors like Vedit and programming became faster
and more efficient.
After 1977 (late in the year) I'd switched ot glass terminal and next year a real
printer (anadex DP800).? When CP/M that was a solid development platform and?
was mostly turnkey (no toggling in a boot).? From then to early 1980 I move from?
CPM V1.3, 1,4 then 2.2 and added third party tools.? The scheme was the box?
with a power switch and maybe reset and mass storage.? Front panel was passe.
AS to CP/M 86 on new hardware... that would be a task and a half.? IT was written
in base 8086 and did run well on any 8086/88 based XT class box.? It would morph
to CCPM.? DRI also had a version for Z8000 and its written in C (K&R dialect) and
that would be easier to port to newer or non x86 hardware.
For those really into it... go here???
also see?
My idea of a compact Z80 system would be 4mhz or faster (10mhz parts are easy to find)
64K ram mappable (and boot) 256K eprom (boot, system, base utilities (small romdisk) and
a larger mass storage such as uSD 1gb is far more than needed.? two serial port such as
Z80 dart).
Allison
|
I had much the same experience, though in addition to the H89 I also found a Kaypro II. I didn't and don't do much in the way of software development, but I did get online with a moderately hacked Turbo Pascal program and a 300baud modem on the H89. Once I moved to the PC, it was strictly appliance computing. I do wonder how hard it would be to make a version of CP/M-86 that would work well on the modern PC, and take advantage of all the memory and storage. I'm probably never going to know.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
A human being should be able to change a diaper, plan an invasion,
butcher a hog, conn a ship, design a building, write a sonnet, balance
accounts, build a wall, set a bone, comfort the dying, take orders,
give orders, cooperate, act alone, solve equations, analyze a new
problem, pitch manure, program a computer, cook a tasty meal, fight
efficiently, die gallantly. Specialization is for insects.
LAZARUS LONG (Robert A. Heinlein)
On Thursday, July 30, 2020, 03:21:57 PM CDT, Lee Hart <leeahart@...> wrote:
ajparent1/kb1gmx wrote:
> There are two forms of CP/M experience:
>? ? Small, slow and cramped typical of early floppies of 120 and 241K size.
>? ? High performance using fast large media (hard disks, IDE, CF, SD).? [snip]
That's a good summary of CP/M usage, Allison. It mirrors my experience
as well.
Early on, CP/M computers with primiive software and floppy disks really
slowed software development. But that's all I had; I didn't know any
better. It sure as heck beat a CPU manufacturer's development system
with paper tape and a teletype! So I was in heaven. :-)
As better CP/M editors, debuggers, assemblers, and compilers were
developed, it became much easier to develop code. Things like the SLR180
assembler and Turbo Pascal were great productivity tools.
Then hard drives and higher CPU clock speeds were added, and the
computer's speed no longer limited your productivity; the only limit was
YOUR speed and creativity!
For me personally, the PC was a setback. It put me back at the bottom of
the learning ladder. It was much slower than my Z80 system (a Heath H89
at the time), and its byzantine architecture made it much harder to use.
I tried, but by the late 1980's I gave up. PCs basically became an
appliance; a platform to run someone else's hardware and software. My
time and talents went into other hobbies (electric cars), and in
continuing to develop new applications for 8-bit microcomputers
professionally; areas where I felt I could still accomplish something.
After I retired, I felt a need to get back to when computers were FUN.
Something a beginner could learn and understand, and build and create
useful things themselves. It givee me a sense of accomplishment you
can't get by buying everything and running someone else's software.
My hope for the Z80MC is to get it to the point where *it* can be a good
platform for developing vintage hardware and software. Done right, it's
going to be easier to use it than try to do it on a PC! You can be
running your CP/M programs even before the PC finishes booting. :-)
Thus, I'm hunting around for a video/terminal application. That's the
obvious missing link.
Lee Hart
--
A designer knows he has achieved perfection not when there is
nothing left to add, but when there is nothing left to take away.
? ? ? ? -- Antoine de Saint Exupery
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
|
ajparent1/kb1gmx wrote: There are two forms of CP/M experience:
Small, slow and cramped typical of early floppies of 120 and 241K size.
High performance using fast large media (hard disks, IDE, CF, SD). [snip] That's a good summary of CP/M usage, Allison. It mirrors my experience as well. Early on, CP/M computers with primiive software and floppy disks really slowed software development. But that's all I had; I didn't know any better. It sure as heck beat a CPU manufacturer's development system with paper tape and a teletype! So I was in heaven. :-) As better CP/M editors, debuggers, assemblers, and compilers were developed, it became much easier to develop code. Things like the SLR180 assembler and Turbo Pascal were great productivity tools. Then hard drives and higher CPU clock speeds were added, and the computer's speed no longer limited your productivity; the only limit was YOUR speed and creativity! For me personally, the PC was a setback. It put me back at the bottom of the learning ladder. It was much slower than my Z80 system (a Heath H89 at the time), and its byzantine architecture made it much harder to use. I tried, but by the late 1980's I gave up. PCs basically became an appliance; a platform to run someone else's hardware and software. My time and talents went into other hobbies (electric cars), and in continuing to develop new applications for 8-bit microcomputers professionally; areas where I felt I could still accomplish something. After I retired, I felt a need to get back to when computers were FUN. Something a beginner could learn and understand, and build and create useful things themselves. It givee me a sense of accomplishment you can't get by buying everything and running someone else's software. My hope for the Z80MC is to get it to the point where *it* can be a good platform for developing vintage hardware and software. Done right, it's going to be easier to use it than try to do it on a PC! You can be running your CP/M programs even before the PC finishes booting. :-) Thus, I'm hunting around for a video/terminal application. That's the obvious missing link. Lee Hart -- A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away. -- Antoine de Saint Exupery -- Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
|
ajparent1/kb1gmx wrote: old analog monitors were pushing hard at 80 chars but crisp at 64...
at 64 chars most editors and apps were easy to live with, but less
tended to really suck... I agree with your reminiscing, Allison. I have an Atari 800 with 32-char screen; its NTSC video is fuzzy and painful to read. I had an Osborne O1, and its 5" 50-char CRT was also poor. I had an S-100 64-char video card with 12" Ball monitor that was very readable. The Kaypro/4 9" 80-char CRT was decent, and my Heath H19/H89 12" 80-char CRT is probably the best of my antiques. Modern LCD monitors are highly variable. Many have poor color NTSC conversion, with lots of artifacts and aliasing. But more expensive large-screen LCDs can be pretty good; they just get overly bulky (a 17" LCD is overkill for CP/M use). before the CTRC part it was mostly TTL and a lot of parts. Yes; brute force circuits. But by 1978-80, Lancaster, Wozniak, Sinclair etc. were showing us video circuits that used finesse and cleverness instead of brute force. That's the philosophy I'm after. How to produce good video without lots of parts or rare/expensive chips. Graphics adds even more... not much graphics in Z80 CP/M applications. Right. But today, people kind of expect/demand graphics. Most early systems that had graphics used "character" graphics; a special character set with graphicsh symbols. If my board can do this, it can emulate the screens of a TRS-80, Kaypro, Heath, VT-100, etc. Since RAM is now cheap and it saves a character generator chip, I can make it a graphics display and "draw" the characters with the Z80, like the Mac did. I picked a 384x192 pixel screen for my Z80-VID design because it allows a 6x8 font to produce a 64-character by 24-line display, or even 80 x 24 with a proportional or ugly 4x8 font. This gives it a programmable font, to better emulate vintage computers, without "pushing" the NTSC bandwidth too far. But... is all this reasonable? Would anyone build or use it? Or does it produce a display that nobody likes? USB is easier to get PS2 is starting to get scarce. Yep. But there are USB-to-PS2 adapters. That provides a path for the guy that wants to use his old USB keyboard. Lee -- A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away. -- Antoine de Saint Exupery -- Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
|
On Wed, Jul 29, 2020 at 11:22 AM, Lee Hart wrote:
I'm not sure how much resolution is "enough". 32, 40, 64, and 80 chars/line were all common. For a small screen, are the lower resolutions OK? The quality of TVs, monitors, and LCDs can limit the bandwidth as much as the video board.
Lee, The old analog monitors were pushing hard at 80 chars but tended to be crisp at 64. The trade is that at 64 chars most editors and apps were easy to live with but less (Osborne at 50chars) it tended to really suck for a lot of aps and editors or program development. The Kaypro used decent monitor (Ball and friends) and at 80 chars looks very good. The bigger issues is before the CTRC part it was mostly TTL and a lot of parts. (scan, row and dot counters), plus rom for the character generators.? Graphics adds even more.? Generally not much in the way of graphics in Z80 CP/M applications.? Things important were the full set of attributes and cursor controls. The IBMPC was pretty much in step with what video was at that time it was MDA to CGA that improved that and morphed into VGA and on. Two things had to happen one was monitors especially color had to go up in resolution and down in price.? Also memory had to become cheap.? The PC with graphics was late 80 or later depending on the budget!? That was pushed by apple as IBMPC didn't have a graphic GUI until windows 3 (yes there was 1 and 2 but they stank up the place).? I still have a? 1998 S7 video cards that did 640x480x8 colors the VGA standard. One problem I've found with LCDs is the NTSC inputs are very picky as to timing or the screen will be offset or have the wiggles and they want NTSC color timing! Finding a RCA or sanyo/panasonic analog monitor is tough!? I have a ball I've kept for some project as they are scarce and it takes three input Vsync, Hsync, and Video and by jumper option any combined flavor of that up to NTSC mono. One set of systems I have is the Visual 1050 system Z80 main cpu and 6502 for the? video that does both bit graphics (320x240 mono) and character modes.? At the time it was done that was 16K of Dram for the bitmap (about 2k for characters). Again USB is easier to get PS2 is starting to get scarce.?? Over all computer video as we know it is a recent thing being less than 2 maybe stretching it 3 decades old.? ?Before that I was using a 21 inch Trinitron and VAX/VMS DECwindows at 1024x1024 color on a MIcroVAX-II/GPX.? That was the tail end of the 80s when the worstation era? [1megapixel, 1MIPS]?and desktop or deskside was the ne plus ultra.
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ajparent1/kb1gmx wrote: Not a fan of TMS9918, hard to get too.
As I have a large collection of CP/M base systems...
S100 several... (Altair, NorthStar, Compupro)
AmproLB+
Kaypro 2 and also 4/84
DEC VT180 (z80 board + Vt100)
Osborne portable
Epson PS-8... A good summary, Allison. I too have a pile of vintage systems to look at, plus I've stared at the schematics of lots more. Learn from the experts! :-) One common thread is that most of the designers were either in tearing hurry, or trying hard to do it on the cheap. When they were in a hurry, we got conservative designs with lots of parts, but poorly optimized (early IBM PC video). When they wanted cheap, we got minimalist hardware that barely worked with serious performance compromises (Sinclair ZX80). I think there is a third approach in-between these two extremes. You can do more with less, if you have time to be thorough and a high degree of skill. The Apple II and early Macintosh computers were examples of this. Not much hardware; but it did a lot; and without the performance compromises (like the video monopolizing the CPU's time). NTSC, Try to find a monitor. I'm aiming for systems that can do NTSC or PAL. If you don't have an old TV or CRT monitor, there are lots of little LCD TVs with NTSC or PAL inputs. S100 and friends use either 64Char x 16line (processor tech VDM-1) and
similar. Later ones use 80x24/25 (just more parts). I'm not sure how much resolution is "enough". 32, 40, 64, and 80 chars/line were all common. For a small screen, are the lower resolutions OK? The quality of TVs, monitors, and LCDs can limit the bandwidth as much as the video board. I happen to like a programmed atmega or two (Grant Searle) as it allows for
VGA, PS2 keyboard. Lots of people do. It's a common approach, and "fashionable" today, especially if you're using it with a modern micro. The above also reflects that if you do video you need a keyboard.
Most common keyboards are now USB. Yes, that is the case. Most people don't want to make a keyboard; they would rather use something they already have. Maybe an old PS2 keyboard, or more likely it's USB. But the whole point of hacking around old computers is that you should be able to interface whatever you like! Not limit yourself to just what the developer had in mind. PS2 is hackable; just about any micro can interface it. USB is much harder; you pretty much need a modern micro to talk to it. Lee Hart -- A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away. -- Antoine de Saint Exupery -- Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
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Bill in OKC too
Lee Hart