English Amiga Board


Go Back   English Amiga Board > Search Forums

Showing results 1 to 40 of 91
Search took 0.03 seconds.
Search: Posts Made By: PeteAU
Forum: Hardware mods 05 April 2018, 13:06
Replies: 356
Views: 50,120
Posted By PeteAU
Even EXRAM is "don't care" on a A500+ because...

Even EXRAM is "don't care" on a A500+ because it's not connected on the motherboard!

I looked for the B52/floppy BMP files but couldn't find them. Maybe I'll check another computer later.

Nice...
Forum: Hardware mods 03 April 2018, 04:45
Replies: 356
Views: 50,120
Posted By PeteAU
Just see post #2 and order your own straight from...

Just see post #2 and order your own straight from China. It's cheap & easy.
Forum: Hardware mods 08 February 2018, 05:11
Replies: 356
Views: 50,120
Posted By PeteAU
No schematic, but gerber files added to post #2...

No schematic, but gerber files added to post #2 (first page). No idea if they work though. Let us know the result.
Forum: Hardware mods 29 January 2018, 09:20
Replies: 356
Views: 50,120
Posted By PeteAU
Screwed? Yes. Do you already have PCBs ordered?...

Screwed? Yes. Do you already have PCBs ordered? Maybe I can dig out a SOJ40 variant I put somewhere.



It's normal for elecrow, but maybe 3 boards are scratched or imperfect?
Forum: Hardware mods 25 January 2018, 09:57
Replies: 356
Views: 50,120
Posted By PeteAU
Join JP9 on the motherboard, otherwise the two...

Join JP9 on the motherboard, otherwise the two RTC chips will fight each other.



You used all CMOS HC (not HCT) chips and it worked? Surprized...
Forum: Hardware mods 11 January 2018, 06:31
Replies: 356
Views: 50,120
Posted By PeteAU
Both my diagram or demolition's would work fine....

Both my diagram or demolition's would work fine. I would solder only 2 chips though.

---

So has somebody combined this with a TF530? Supposedly 4.0-4.5 MB RAM is plenty for WHDLoad?
Forum: Hardware mods 25 November 2017, 10:12
Replies: 356
Views: 50,120
Posted By PeteAU
My post actually says "Battery Holder: Some cheap...

My post actually says "Battery Holder: Some cheap ebay one.". There is no part number. They're $1 for ten.
Forum: Hardware mods 15 November 2017, 10:00
Replies: 356
Views: 50,120
Posted By PeteAU
Selecting 0.5 CHIP on the Gary board doesn't...

Selecting 0.5 CHIP on the Gary board doesn't actually make it happen, you're just informing it you have 0.5. To really get 0.5MB you would need to return JP2 (motherboard) to the original factory...
Forum: Hardware mods 04 November 2017, 03:36
Replies: 356
Views: 50,120
Posted By PeteAU
This is what I would do: C11: none C12: 100nF...

This is what I would do:
C11: none
C12: 100nF 0805
C13: none
C19: 4.7uF tantalum (10 volts or better)

That's pretty much exactly Commodore's circuit in the A501.
Forum: Hardware mods 03 November 2017, 13:42
Replies: 356
Views: 50,120
Posted By PeteAU
Nice! I bought all the parts for your IDE board...

Nice! I bought all the parts for your IDE board too, one day I'll build it. What's this flat-flex cable you have there?



I *think* you can only use the board as chipram on the A500+.
But maybe...
Forum: Hardware mods 03 November 2017, 11:01
Replies: 356
Views: 50,120
Posted By PeteAU
Dumb question: Did you close RAM enable jumper?...

Dumb question: Did you close RAM enable jumper? It's needed for any slow RAM. Have you tried 0.5 CHIP + 1.0MB SLOW settings on gary adapter? You could also try swapping the two SEL wires.
Forum: Hardware mods 20 October 2017, 12:07
Replies: 356
Views: 50,120
Posted By PeteAU
If you convert your 8A to a 1MB A500+ then 74F139...

If you convert your 8A to a 1MB A500+ then 74F139 and Gary Adapter are not used!
Edit: I miss-understood, you're putting a 139 on the motherboard for conversion.

Yes I reckon it's easier to put...
Forum: Hardware mods 20 October 2017, 11:35
Replies: 356
Views: 50,120
Posted By PeteAU
That wouldn't work very well thru the trapdoor....

That wouldn't work very well thru the trapdoor. You need to add the 0.5MB onboard DIP chips and turn it into a realistic A500+. Then you can use this board to add another 1.0 MB (2.0 MB total CHIP...
Forum: Hardware mods 29 September 2017, 07:31
Replies: 11
Views: 1,112
Posted By PeteAU
It might work, but it depends what chip is inside...

It might work, but it depends what chip is inside the mouse. You've got to crack open the case and look.

I did it with this PS2 mouse and it works well.
Forum: Hardware mods 23 September 2017, 01:44
Replies: 356
Views: 50,120
Posted By PeteAU
My only comment is that's too expensive. The...

My only comment is that's too expensive. The sockets, connectors and RTC could be much cheaper elsewhere.

P.S. I have posted rev B.6 (1st page). This should be finished for 2017 :)
Forum: Hardware mods 22 September 2017, 11:36
Replies: 356
Views: 50,120
Posted By PeteAU
Just 100nF for the RTC isn't enough. When you...

Just 100nF for the RTC isn't enough. When you flick the power switch off, the voltage on the RTC briefly dips way down (around 2V) and it will sometimes forget time/date. I watched it on a scope. It...
Forum: Hardware mods 20 September 2017, 12:19
Replies: 356
Views: 50,120
Posted By PeteAU
IMO C3, C6, C23, C11 are not needed - I run...

IMO C3, C6, C23, C11 are not needed - I run happily without them. Pads are there just in-case.

C13/C19 are alternatives. Only one of them is needed. Any value >=4.7uF will be fine. 2.2uF ceramic...
Forum: Hardware mods 19 September 2017, 13:51
Replies: 356
Views: 50,120
Posted By PeteAU
I successfully use: 74F00, 74HCT74 and 74F139....

I successfully use: 74F00, 74HCT74 and 74F139. Seems strange they wouldn't work for you. Are you sure it wasn't "HC" by accident?



Will be fine! It's a tiny change Mathesar suggested but won't...
Forum: Hardware mods 19 September 2017, 10:58
Replies: 356
Views: 50,120
Posted By PeteAU
Maybe there'll be a B.6, Mathesar pointed out...

Maybe there'll be a B.6, Mathesar pointed out another thing, it never ends :rolleyes

The main board BOM is unchanged. I would recommend the RTC62421 (search AliExpress).
Just another 74HCT00 and...
Forum: Hardware mods 18 September 2017, 11:31
Replies: 356
Views: 50,120
Posted By PeteAU
All-right, Rev B.5 is posted (see 2nd post, first...

All-right, Rev B.5 is posted (see 2nd post, first page).
Unless there's a major screw up, that's it for this year.
Let us know if you build it.
Forum: Hardware mods 14 September 2017, 13:07
Replies: 356
Views: 50,120
Posted By PeteAU
These are good points. Do you want to make the...

These are good points. Do you want to make the changes or does clicking things in Eagle make you feel ill? ;)

In the meantime I posted rev B.4 where I managed to remove 2 vias on the gary adapter...
Forum: Hardware mods 14 September 2017, 03:54
Replies: 356
Views: 50,120
Posted By PeteAU
The outline file is .GML and looks fine to me....

The outline file is .GML and looks fine to me. The unrouted 19 is just some signals that we don't want to route from the main board to gary.
Go on, splash the $4.90+post and give it a go :)
Forum: Hardware mods 13 September 2017, 12:56
Replies: 356
Views: 50,120
Posted By PeteAU
New revision of the board, somebody plz check it

Hi,

I combined Mathesar's new gary adapter, redrawn by Mq666 into one board:

(links removed)

Changes:
- Added a jumper for RTC enable.
- Added a footprint for SMD RTC chip, so you can...
Forum: Hardware mods 12 September 2017, 11:25
Replies: 356
Views: 50,120
Posted By PeteAU
No worries. They can be sold for profit, as long...

No worries. They can be sold for profit, as long as you release the modified design if somebody asks.



Will they work as a drop-in replacement of the original RTC chip?[/QUOTE]

Kind of, you...
Forum: Hardware mods 12 September 2017, 01:55
Replies: 356
Views: 50,120
Posted By PeteAU
Are you planning to make & sell these on an...

Are you planning to make & sell these on an online store? Just my hunch :)
Use a RTC-72421 & remove the crystal, they're calibration free and more accurate.
Forum: Hardware mods 10 September 2017, 10:50
Replies: 356
Views: 50,120
Posted By PeteAU
Actually it is a small bug on your board, you're...

Actually it is a small bug on your board, you're missing a trace to U1 from the middle pad. It's sometimes handy for testing plain old 512K boards without having to remove the gary adapter.

If you...
Forum: Hardware mods 09 September 2017, 14:03
Replies: 356
Views: 50,120
Posted By PeteAU
Are you sure your /XRAM (enable) isn't cut on the...

Are you sure your /XRAM (enable) isn't cut on the motherboard JP7A? People often did that in the old days for 1MB CHIP mod.

If I remove my enable jumper, it ends up mirroring C0 with D0 and...
Forum: Hardware mods 08 September 2017, 15:37
Replies: 356
Views: 50,120
Posted By PeteAU
I built my revC, it's working. Gary from '87.

I built my revC, it's working. Gary from '87.
Forum: Hardware mods 08 September 2017, 11:07
Replies: 356
Views: 50,120
Posted By PeteAU
I didn't build my revC adapter yet, I'll see what...

I didn't build my revC adapter yet, I'll see what it does with my Toshiba gary.

Disabling $D0 (by jumper) actually effects the RGAE and RAMEN for $10 (non-existent chip ram above 1MB). But...
Forum: Hardware mods 07 September 2017, 10:59
Replies: 356
Views: 50,120
Posted By PeteAU
It's very confusing that 1M/1M works perfectly...

It's very confusing that 1M/1M works perfectly for you. Do pins 7 & 9 of 74F139 look good?
Forum: Hardware mods 06 September 2017, 11:10
Replies: 356
Views: 50,120
Posted By PeteAU
That's a pretty nice & clear description, errors...

That's a pretty nice & clear description, errors are always in the D00000-D7FFFF area right? I assume you linked all 4 chips to RAS1?

Maybe a manufacturing fault on the U4 PCB area? I've got one...
Forum: Hardware mods 28 August 2017, 14:24
Replies: 356
Views: 50,120
Posted By PeteAU
You missed out on the fun of green screens and...

You missed out on the fun of green screens and such like.
So, does kickstart know to prioritise the fast ram ahead of the 1.5mb slow ram?
Close up photo of your boards?
Forum: Hardware mods 15 August 2017, 07:09
Replies: 356
Views: 50,120
Posted By PeteAU
How about kickstart memory scan, it succeeds?

How about kickstart memory scan, it succeeds?
Forum: Hardware mods 11 August 2017, 15:39
Replies: 356
Views: 50,120
Posted By PeteAU
Here's my stab at dragmar's possible problem: ...

Here's my stab at dragmar's possible problem:

Did you cut the links "cut these for gary adapter" right?

How is JP2 on A500 motherboard, back to default right?

Maybe U3 really has 1 bad...
Forum: Hardware mods 01 August 2017, 05:01
Replies: 12
Views: 1,480
Posted By PeteAU
Believe it or not, I flashed it successfully...

Believe it or not, I flashed it successfully using STMFlashLoader.exe under WINE. I used a nice and slow 9600 baud rate.

Wasn't there also a jumper on the board to unlock flashing?
Forum: Hardware mods 31 July 2017, 13:20
Replies: 356
Views: 50,120
Posted By PeteAU
Got Mathesar's improved Garry adapter. Looks...

Got Mathesar's improved Garry adapter. Looks good, just got to find time to build it :xmas
Forum: Hardware mods 25 July 2017, 05:53
Replies: 356
Views: 50,120
Posted By PeteAU
There's enough pads to put 1, 2 or 3 decoupling...

There's enough pads to put 1, 2 or 3 decoupling caps for each DRAM chip. I'm not going to scientifically measure how many you need, but probably 2 per chip is plenty.
So populate C1, C2, C4, C5, C7,...
Forum: Hardware mods 24 July 2017, 15:15
Replies: 356
Views: 50,120
Posted By PeteAU
1. JP4 on the adapter can disable it. 2. I...

1. JP4 on the adapter can disable it.

2. I didn't make such a file. Maybe one day I'll join Mathesar's adapter and the original board into one gerber. Removing the adapter doesn't save you any...
Forum: Hardware mods 21 July 2017, 13:48
Replies: 356
Views: 50,120
Posted By PeteAU
No, it's 1M x 16. That's right, each...

No, it's 1M x 16.



That's right, each chip is 2MB (1Mx16-bit). You're using exactly the same SIMM as mine, just a different brand of chips on board.
Forum: Hardware mods 21 July 2017, 03:04
Replies: 356
Views: 50,120
Posted By PeteAU
They look perfectly good. 8 rams per Simm? You...

They look perfectly good. 8 rams per Simm? You are lucky.
Showing results 1 to 40 of 91

 
Forum Jump

All times are GMT +2. The time now is 17:42.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Page generated in 0.18181 seconds with 9 queries