Search found 65 matches

by tzok
Fri Sep 21, 2018 8:37 pm
Forum: RTC (Real time clock)
Topic: Desoldering Falcon NVRAM
Replies: 11
Views: 858

Re: Desoldering Falcon NVRAM

Working replacement chip is DS12887+, and I haven't found here information how to reset/initialize new chip, so:
Falcon 030: Alternate+Control+Right Shift+Undo
CT060: Control+Alternate+Undo
...during boot, before RAM test.
by tzok
Fri Sep 21, 2018 11:41 am
Forum: STF REMAKE PROJECT
Topic: 12V needed anymore ?
Replies: 6
Views: 229

Re: 12V needed anymore ?

There is a chance that UBEswitch will be fine with 5V on 12V rail... As for floppies - even the Sony FDD used on latter STes didn't use 12V.

The +/-12V has been used for RS232 only on early STs with external power adapter.
by tzok
Fri Sep 14, 2018 11:12 pm
Forum: RTC (Real time clock)
Topic: Desoldering Falcon NVRAM
Replies: 11
Views: 858

Re: Desoldering Falcon NVRAM

As far as I know Falcon uses a standard DALLAS DS1287/DS1387 RTC or a compatible replacement. They are widely used in PC and some other equipment, like HP 5450x DSOs (actually there is a DS1235). There is a relatively easy hack to connect an external battery to this chip: http://www.mcamafia.de/mcap...
by tzok
Thu Sep 13, 2018 2:45 pm
Forum: RTC (Real time clock)
Topic: no-software internal RTC
Replies: 46
Views: 2483

Re: no-software internal RTC

I've experimentally measured the delay introduced by my ST IKBD RTC module:
SDS00048.png
SDS00048.png (164.6 KiB) Viewed 91 times
dT = 1.28ms
For comparison - screen redraw time in color mode is 20ms.
by tzok
Wed Sep 12, 2018 10:09 pm
Forum: PSU (power supplies)
Topic: PSU failure images
Replies: 2
Views: 512

Re: PSU failure images

The latter one is tricky to spot, as they have a dome-shaped plastic cover on top, so you never know if it's the capacitor "ready to explode" or just the cap looks like this.
by tzok
Wed Sep 12, 2018 10:03 pm
Forum: PSU (power supplies)
Topic: Replacement PSU for STf/STe
Replies: 0
Views: 59

Replacement PSU for STf/STe

I've managed to fit a MeanWell RT-65B PSU into the STf case in place of original PSU. It works fine on my "noisy" STf, even better (less noise) than my original STe PSU. This is a 65W switchmode PSU with 5V/5.0A, 12V/2.8A and -12V/0.5A. It barely fits the case. I had to remove its original aluminum ...
by tzok
Tue Sep 11, 2018 4:00 pm
Forum: SOFTWARE PROGRAMMING & DISCUSSION
Topic: TOS105 ROM
Replies: 59
Views: 2302

Re: TOS105 ROM

How do you want to distribute your modified TOSes? Do you plan electronic distribution? I'd be interested in such.
I'd be interested in 1.66i UK, but without your RTC fix (13), and without custom icons (9). I'd also much more like the old black, simple Atari logo from 14UKV3D, than this new, blue one.
by tzok
Tue Sep 11, 2018 2:51 pm
Forum: RTC (Real time clock)
Topic: no-software internal RTC
Replies: 46
Views: 2483

Re: no-software internal RTC

I've done some further tests and: * on STf(m) with TOS 1.00 - 1.04 it works using ST Control Panel (CONTROL.ACC), Panel is used both for synchronizing ST Clock with IKBD Clock on reboot and adjusting the clock, * on STe with TOS 1.06/1.62 using STE_FIX.PRG and STE Control Panel (CONTROL.ACC), STE_FI...
by tzok
Mon Sep 10, 2018 9:52 pm
Forum: HARDWARE ISSUES
Topic: STF stuck in boot loop
Replies: 13
Views: 368

Re: STF stuck in boot loop

Virtually any 001/010 Flash will be fine. I was using Intel P28F001, SST 29EE010, SST 39SF020, and Winbond W49F020. Mostly they were 150ns and 70ns versions. I also have 39SF040, but didn't try them (they would fit 4 versions of TOS).
by tzok
Mon Sep 10, 2018 6:17 pm
Forum: HARDWARE ISSUES
Topic: STF stuck in boot loop
Replies: 13
Views: 368

Re: STF stuck in boot loop

Unfortunately, every option I can find seems to be quite a bit more expensive than just buying a complete ST. I mean, the ROMS cost a few euros a piece and I'd need 6. And I don't have a programmer... If you have a board revision that has all 6 ROMs in one row, you may easily replace them by two 1M...