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Apple Imagewriter II Restoration
Posted by: trag on 2015-03-02 11:27:39
So.. No love for the IW II then? I see.... 
I'm quite fond of mine.   I have the cut-sheet feeder, which is very cool, and probably back in the late 90s I tracked down the MacPalette II print driver for it so that I could get millions of colors out of the four color ribbon.

The images are pretty good.  When you consider the hardware they're coming from, the images are amazing.
Posted by: techknight on 2015-03-04 17:09:16
I decided to fire it up today! Well, I believe one or two of the top pins arnt firing, So i need to figure out why that is. 

the pin driver circuitry is potted in epoxy, so that route isnt going to be an easy task, itll be easier if I just trace down the continuity between the drive head, and the board through the ribbon cable to make sure there are on breaks there. 
Posted by: aplmak on 2015-03-04 20:44:42
Techknight… Looks like I have to do mine as well… Thanks for the advice.. I've got a few.. plus the original image writers.. so that's my next project as well… capacitors are just a pain in the neck!!!! I plan on storing my TAM's for a long period of time.. I know the SMD caps are fine now but I don't want to pull them out in 10-20 years and find they have leaked… suggestions??? Should I recap them??

Matt
Posted by: techknight on 2015-03-05 05:01:04
Yep because I found one starting to leak on my TAM. It was one closest to the heat sources.
Posted by: techknight on 2015-03-05 05:51:26
Here we go. Print head is now functioning correctly.

I had to soak it in alcohol and clean all the spooge out of the pin guides.

Before:

1425563702657.jpg

After:

20150305_085013.jpg
Posted by: trag on 2015-03-05 11:24:06
Here we go. Print head is now functioning correctly.

I had to soak it in alcohol and clean all the spooge out of the pin guides.
Heh.  Beat me to it.  I was going to suggest that.   The pins get stuck as residue dries out and turns into something between glue and paper machier.
Posted by: techknight on 2015-03-05 19:49:36
Yea i figured that had something to do with it. 

Only thing left to do now, is lube up the key joints in the mechanism, and then retrobright it. 

Then itll be good as new. 
Posted by: NJRoadfan on 2015-03-05 20:33:56
If you need a torture test, I can dump a printout at 160x144dpi.... in color.... that you can feed via serial.
Posted by: raoulduke on 2015-03-06 13:23:21
Hey this isn't strictly relevant but this guy has just reposted an ad from at least a month ago...  I don't know if anyone's interested.  I'm pretty sure he hasn't tested it, so it could be a repository for parts if it's in even worse shape.  I have no printers so I'd go for it if it weren't so big.

http://cnj.craigslist.org/sys/4887034432.html
Posted by: techknight on 2015-03-06 15:07:11
If you need a torture test, I can dump a printout at 160x144dpi.... in color.... that you can feed via serial.
Oh?
Posted by: NJRoadfan on 2015-03-07 20:06:00
The attached dump is raw output from an Apple IIgs application, it should print out a picture in color at 160x144dpi. It is an 8-bit binary file since it contains image data.

If possible, can you scan the page with a flatbed and post it here, I want to compare it with something here.

iwdump.zip
Posted by: techknight on 2015-03-08 15:54:58
I didnt think the apple imagewriter II could do regular serial? I thought it was localtalk. Guess not 😉

Posted by: NJRoadfan on 2015-03-08 15:57:59
Localtalk was optional, that port on the back is RS-422/232 serial.
Posted by: techknight on 2015-03-08 16:07:47
Ah. Yea, I wasnt aware of that. 

But I dont know the baud rate/flow control or anything to send that file? 
Posted by: NJRoadfan on 2015-03-08 16:33:38
Default jumpers should be set at 9600 baud (SW 2-1 and 2-2 CLOSED) and hardware flow control (SW2-3 OPEN), 8-N-1 for the rest.
Posted by: techknight on 2015-03-08 17:24:02
That means I have to make another crazy homemade cable hanging around. ugh. lol. 

Might be easier to write a simple binary serial output app for the Mac. 
Posted by: NJRoadfan on 2015-03-08 18:07:39
I got that too:

Mini-DIN 8   DB-25    DB-9

1  DSR        6**     6

1  DCD        8**     1

2  DTR       20       4

3  RxD        3       2

4* GND        7       5

5  TxD        2       3

6 NC

7 NC

8* GND

Shield       Shield

*Connect together at Mini-DIN 8

**Connect together at DB-25

DB-9 specs weren't in the Imagewriter manual, I looked up the pin out online.
Posted by: techknight on 2015-03-08 18:46:23
Then I am sure you know this question too: 

How to send the binary via serial and flow control? I have written alot of serial based software before, But never in any case I had to use flow control for anything. 
Posted by: NJRoadfan on 2015-03-08 19:15:50
I have never done it in C, but this guy has done it in QBasic on the receive end: http://ptouchman.blogspot.hk/2014/07/serial-flow-control-rts-in-qbasic.html

You need a loop of some sort that stops transmitting when the DTR line is set to false and resumes when its set to true. I think you can send the contents of the file "raw" to the serial port using a terminal program too. Whats interesting is Apple's programming examples in the IW II technical reference don't bother with flow control at all. They just open up the serial port and write characters to it.
Posted by: techknight on 2015-03-08 19:52:17
Thats good because I dont know C. lol. I am a BASIC guy. Well, the modern forms of it. I dont know too much about the older forms as it was slightly different than what I am used to, today. 
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