• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

Mac iisi monitor problem

Papichulo

Well-known member
I cant get the mac iisi to show a image. I have a lcd and a 8 pin pnp adapter to vga that wont work on any setting. Do i need a different dip switch? Thanks

 

jessenator

Well-known member
What sync setting are you using on the adapter? (usually the last 4 dip switches, depending on the adapter) Also, does your adapter have a little documentation?

My ViewSonic adapter (8-pin) has the following instructions, as well as limitations on which model can do what resolution:
A7VFDQ5.jpg.c9b283a76281b4ff39486545775d8a76.jpg


SvgKNE5.jpg.1c1be1f4feaf9e0a5bd4f77db2a94f45.jpg


My guess is one of those duplicate IIci's on the chart should be a IIsi, so for me I can't go larger than 640x480

 

Trash80toHP_Mini

NIGHT STALKER
It's likely not the adapter that's your problem. What display are you attempting to drive? If it's VGA@60Hz, there's no way a IIsi can drive it. You need an Apple monitor from the day or a good MultiSync display. All the IIsi outputs are "flicker free" Apple refresh rates at anything BUT the 60MHz VGA standard.

The top page above tells much of the tale about that incompatibility. Viewsonic is defining Apple's whackdoodle frequencies and telling the user to select a display (multisync) that supports those frequencies.

 
Last edited by a moderator:

Papichulo

Well-known member
Well i have a planar pe 150M monitor it recognozes my performa and other macs but not the iisi. I dont know if ots multisync or not. Will a lcd screen thats multisync fix the problem? I really don't understand this

 

jessenator

Well-known member
Yes. Your Performa and possibly newer macs (don't know what those are) have internal video that is a bit more friendly to the PC world's standards, and are capable of driving those refresh rates, which is why they work.

Like Trash80 said, older Macs had, let's say non-traditional, refresh rates, or at least ones that didn't match the standards of the PC world, which were very widespread and somewhat standardized in that world. I.e. Apple Macintosh computers were meant to run on Apple Macintosh monitors (or monitors made for the specs of that era: Radius, RasterOps, etc., but even they sometimes required their own NuBus cards).

A multisync monitor might solve the issue, but for what it's worth, I've had only limited luck with my multi-sync LCDs on my older Macs, even with an adapter. I'm thinking of getting one like this: https://www.ebay.com/itm/273978718538 to replace the DIP version, but even then I'm thinking machines like my IIci will probably only work well on my fixed-resolution AppleColor 13" display.

 

Papichulo

Well-known member
I dont think the monitor has anything to do with ot because some guy on youtube used a lcd with a iisi and its the same specs as my lcd monitor . 

 

jessenator

Well-known member
Well I looked up the manual, and it does list the following. The "MAC 13" Mode" makes me think it should be plug and play
W847LLl.png.420eaad1f380291a608c915db2cb7027.png


So it should actually be able to display correctly, no other special DIP adapter required, if that timing chart is correct.  Perhaps a plain DB-15 to DA-15 adapter would get you rolling. It could be that the DIP adapter is interfering with the monitors built-in ability to time correctly to the Mac output.

 
Last edited by a moderator:

mattsoft

Well-known member
The IIsi needs a monitor that can sync on green. It will not work on a VGA monitor that expects discrete H/V sync signals or composite sync. It will not work with one of those "timings" adapter either. Your best bet is finding a CRT or LCD that can SOG.

 
Last edited by a moderator:

Papichulo

Well-known member
Thanks for that info! I just ordered the 15 pin dip switch and the other sync switch you suggested. If that dont work then its the monitor. That monitor really can support alot!

 

Trash80toHP_Mini

NIGHT STALKER
Sounds like a plan. Checked the IIsi DevNote:

On-board video
In addition to the existing NuBus video options, a new video
solution has been built into the Macintosh IIsi computer, supporting
the Macintosh II 12-inch B&W, 12-inch and
13-inch RGB monitors and the 15-inch B&W portrait monitor. The
12-inch and 13-inch monitors are supported at up to 8 bits per pixel
(256 colors or shades of gray) and the
15-inch portrait monitor is supported at up to 4 bits per pixel (16
grays).
The video signals are generated by the Apple custom RAM-Based
Video (RBV) chip and are driven through a combination color
lookup table (CLUT) and video digital to analog converter (VDAC)
chip. Each monitor identifies itself by grounding certain pins on the
RBV causing it to automatically select the appropriate pixel clock and
sync timing parameters. See “Video Cables” later in this chapter for
cable wiring details.
When an unknown monitor (or no monitor) is plugged in, on-board
video is halted. As shown in Table 4-1, the monitor.ID bits can
specify eight possible combinations, each of which may indicate a
particular monitor.

You weren't getting the "Over Range" indication on p.10 of the manual? Shouldn't be, sounds like a very capable multisync. If you're getting no signal, the adapter/setting is the problem. Sense lines for one of those supported resolutions need to be detected at startup or the IIsi won't buffer the first MB of RAM for using part of it as the video buffer. Other than 4bit Portrait, the IIsi is sorely lacking in the video output department.

 

Papichulo

Well-known member
Sounds like a plan. Checked the IIsi DevNote:

On-board video
In addition to the existing NuBus video options, a new video
solution has been built into the Macintosh IIsi computer, supporting
the Macintosh II 12-inch B&W, 12-inch and
13-inch RGB monitors and the 15-inch B&W portrait monitor. The
12-inch and 13-inch monitors are supported at up to 8 bits per pixel
(256 colors or shades of gray) and the
15-inch portrait monitor is supported at up to 4 bits per pixel (16
grays).
The video signals are generated by the Apple custom RAM-Based
Video (RBV) chip and are driven through a combination color
lookup table (CLUT) and video digital to analog converter (VDAC)
chip. Each monitor identifies itself by grounding certain pins on the
RBV causing it to automatically select the appropriate pixel clock and
sync timing parameters. See “Video Cables” later in this chapter for
cable wiring details.
When an unknown monitor (or no monitor) is plugged in, on-board
video is halted. As shown in Table 4-1, the monitor.ID bits can
specify eight possible combinations, each of which may indicate a
particular monitor.

You weren't getting the "Over Range" indication on p.10 of the manual? Shouldn't be, sounds like a very capable multisync. If you're getting no signal, the adapter/setting is the problem. Sense lines for one of those supported resolutions need to be detected at startup or the IIsi won't buffer the first MB of RAM for using part of it as the video buffer. Other than 4bit Portrait, the IIsi is sorely lacking in the video output department.
I was getting the over range on the monitor. So this monitor is multisync? So it supports sync on green? 

 

Trash80toHP_Mini

NIGHT STALKER
Curiouser and curiouser? If you're getting Over Range, the IIsi appears to be outputting "something" and the display should support up to a 75Hz refresh rate according to the manual. While everything is set up and you're getting that indication, do a screen shot. That dumps contents of the video buffer into a Pict file on the boot drive. Double click "Picture 1" and it'll open up in Simpletext to see what it looks like, if anything.

 

Papichulo

Well-known member
Sounds like a plan. Checked the IIsi DevNote:

On-board video
In addition to the existing NuBus video options, a new video
solution has been built into the Macintosh IIsi computer, supporting
the Macintosh II 12-inch B&W, 12-inch and
13-inch RGB monitors and the 15-inch B&W portrait monitor. The
12-inch and 13-inch monitors are supported at up to 8 bits per pixel
(256 colors or shades of gray) and the
15-inch portrait monitor is supported at up to 4 bits per pixel (16
grays).
The video signals are generated by the Apple custom RAM-Based
Video (RBV) chip and are driven through a combination color
lookup table (CLUT) and video digital to analog converter (VDAC)
chip. Each monitor identifies itself by grounding certain pins on the
RBV causing it to automatically select the appropriate pixel clock and
sync timing parameters. See “Video Cables” later in this chapter for
cable wiring details.
When an unknown monitor (or no monitor) is plugged in, on-board
video is halted. As shown in Table 4-1, the monitor.ID bits can
specify eight possible combinations, each of which may indicate a
particular monitor.

You weren't getting the "Over Range" indication on p.10 of the manual? Shouldn't be, sounds like a very capable multisync. If you're getting no signal, the adapter/setting is the problem. Sense lines for one of those supported resolutions need to be detected at startup or the IIsi won't buffer the first MB of RAM for using part of it as the video buffer. Other than 4bit Portrait, the IIsi is sorely lacking in the video output department.
Well i tried that putting my performas 7.5.5 hd in the iisi and it turned on but the hard drive just hangs. Its been recapped but theres no sound so theres no way to know whats going on. 

 

Trash80toHP_Mini

NIGHT STALKER
I wonder if a minimal system install on a floppy would leave enough space available for the screen shot? Hopefully you'll get the video up when setting up one of your new adapters, but with no sound out, you may be having more problems than just the video. Removing any RAM SIMMs is probably the first thing I'd do. Then I'd try cleaning the speaker contacts, no startup chime could mean it's not POSTing. Not as problematic of easy as LC contacts. Maybe swap in any other compatible speaker that you might have?  I'd also check that all the caps were installed in the proper orientation as well..

It's too bad macmetex' buckets of inexpensive Radius Color Pivot II/IIsi ran dry. If you can find or already have an SE/30 Vidcard, that should work just fine in the IIsi.

Wait and see (arrival of the new adapters) isn't my style, I'd fiddle around with it in the meantime. [}:)]

 
Last edited by a moderator:

Papichulo

Well-known member
Ok so i got the plug you reccomened and it works! Unfortunately the screen is just white and it wont boot. The ram modules are different and that may be the reason but i dont really know. Would fixing the ram fix the machine?

 

jessenator

Well-known member
Are you sure they're different values and not just different configurations? I.e. number of chips per SIMM?
 
In the event they're actually different values, that would definitely pose a problem. Here's the IIsi' page from the memory guide:
owTDjXm.jpg.dbfe1efdfb3bf59548b9f87e8f03d2c0.jpg

 
You do need to install all identical (value) SIMMs. You could try to pull the RAM and see what happens. It might not boot into the os all the way, but you could see if that solves the video issue. If it clears up, your ram is probably the culprit.
 
Edit: i should also ask, has the board been recapped? Does it still chime?
 
Last edited by a moderator:

Papichulo

Well-known member
Are you sure they're different values and not just different configurations? I.e. number of chips per SIMM?
 
In the event they're actually different values, that would definitely pose a problem. Here's the IIsi' page from the memory guide:

 
You do need to install all identical (value) SIMMs. You could try to pull the RAM and see what happens. It might not boot into the os all the way, but you could see if that solves the video issue. If it clears up, your ram is probably the culprit.
 
Edit: i should also ask, has the board been recapped? Does it still chime?
Its been cleaned almost 10 times since i had it and whoever had it before really cleaned the board and recapped it. Same thing if i remove all the ram. If it has 1mb on the logic board why wont it boot? The rom chips are on the board to. Theres no sound at all the speaker just pops when turning it on. External speakers wont work either.

 
Last edited by a moderator:

jessenator

Well-known member
If it has 1mb on the logic board why wont it boot
Well it might boot system 6.0.7 all the way to the finder, but it uses part-to-all of that 1 MB for video. Another thing to try for no sound is check the contacts on the board for the speaker, they were notoriously terrible for the original LC as well, so they switched to a pin header for the LC II. You can usually clean them with a mechanical pencil eraser or some cotton swabs and alcohol.

The white screen is a symptom of a larger problem, though. I'd check the traces on the board, front and back, to see if any of them are broken.

So was it ever booting properly since you've had it?

 

Papichulo

Well-known member
I tried all that its definetely messed up. No broken traces and the board cant be any cleaner.  The only thing i can think is it had really bad leakage before the previous owner recapped it and shorted out the rom chips or something. I dont want to keep spending money on this thing lol. The power supply, fan works well though 

 
Top