ST RTC EXTERNAL BETA - WIP

Current solutions and designs.
Post Reply
User avatar
exxos
Site Admin
Posts: 2575
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

ST RTC EXTERNAL BETA - WIP

Post by exxos » Sun Aug 20, 2017 10:50 pm

IMG_1746.JPG
IMG_1746.JPG (384.74 KiB) Viewed 753 times
IMG_1744.JPG
IMG_1744.JPG (357.96 KiB) Viewed 753 times
Uses the Internal RTC module on a cartridge adapter PCB. This design can be used as a pass-through cartridge so other cartridges can be plugged in without causing issues.

This design is currently under testing and is not yet on sale.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

User avatar
exxos
Site Admin
Posts: 2575
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: ST RTC EXTERNAL BETA - WIP

Post by exxos » Mon Sep 04, 2017 1:01 pm

1.jpg
1.jpg (63.51 KiB) Viewed 710 times
New revision PCB with fixed holes. "Through" port tested and working fine.

2.jpg
2.jpg (25.9 KiB) Viewed 710 times
This is the software I am using.

3.jpg
3.jpg (25.06 KiB) Viewed 710 times
The RTC cart was on my desk for some weeks, and held the time perfectly!


I need to do a slight revision on the cartridge connector, it probably needs to stick out further away from the pcb so it "fits into" the next cartridge.

If anyone has the original RTC cart with the "pass through port" can you take a image of it.. I'm assuming the connector itself must stick out beyond the plastic case in order to slot into the next cartridge..

I am also selling 2 of these PCB's... viewtopic.php?f=11&t=191#p879

Seeing how expensive these are to make in low qty, I am not sure if I will produce these. This is the 3rd batch so its cost almost £200 in test boards already. That price would have to be included in the final PCB sale price, so I think its just going to cost to much to bring these into production and stock them :(
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

tzok
Posts: 21
Joined: Sat Dec 30, 2017 2:27 pm

Re: ST RTC EXTERNAL BETA - WIP

Post by tzok » Sat Dec 30, 2017 2:31 pm

Would it be possible to put the EEPROM on the board which would contain the drivers/accessory for the RTC?

User avatar
Maeke
Posts: 208
Joined: Thu Aug 17, 2017 3:09 pm

Re: ST RTC EXTERNAL BETA - WIP

Post by Maeke » Sat Dec 30, 2017 5:32 pm

tzok wrote:
Sat Dec 30, 2017 2:31 pm
Would it be possible to put the EEPROM on the board which would contain the drivers/accessory for the RTC?
If you mean the tos, nop. I don't see exxos doing this because his boosters work with theyr own sets of tos eeprom, the tos needs to be boosted too.
And if the rtc has been made this way, it's to keep compatibility with the ste booster, the rtc's ic never worked when the cpu and the tos were at 32Mhz, except when connected to the cartridge port.
And there is also the memory map to consider.

Edit: oups misread!
If i take too long to reply, sorry my cat is sleeping on my laps.

User avatar
exxos
Site Admin
Posts: 2575
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: ST RTC EXTERNAL BETA - WIP

Post by exxos » Sat Dec 30, 2017 6:24 pm

tzok wrote:
Sat Dec 30, 2017 2:31 pm
Would it be possible to put the EEPROM on the board which would contain the drivers/accessory for the RTC?
There are cartridges which can hold some small software on ROM. But I don't think its a simple thing to do. IMO Wouldn't be worth the time involved in creating it just for the sake of a program which can run in auto folder.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

tzok
Posts: 21
Joined: Sat Dec 30, 2017 2:27 pm

Re: ST RTC EXTERNAL BETA - WIP

Post by tzok » Sat Jan 13, 2018 7:12 pm

Coding itself is a problem? Because you may just wire the parallel (E)EPROM to the ROM port and basically that is all. Also - the Atari ST actually has the RTC, but it doesn't have the battery backup. As far as I remember the keyboard controller is responsible for providing the RTC functionality. It would be nice to have a clock set without need of any additional software. A kind of KBD pass-through module, that would initialize the original RTC after power-on. I don't have any UltraSatan/CosmosEx (the're way too expensive for me), I only have STE with external Gotek and (rarely used) Megadrive 60 (I think there was an option for a battery backed-up SCSI clock for Megadrive).

User avatar
exxos
Site Admin
Posts: 2575
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: ST RTC EXTERNAL BETA - WIP

Post by exxos » Sat Jan 13, 2018 8:48 pm

Wiring to the ROM port is easy, but how are you going to get the software to run from the ROMs ? You cant just copy files to the eproms and have them work. It would take some work to adapt the software to cartridge, I can't see anyone putting the time into that when the program is small enough to run from floppy. Also creates a lot of work in adapting the hardware.

You can battery backup the keyboard, have seen it done. But is rather power hungry to power the keyboard chip. If you want super cheap, then sure do that method.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

tzok
Posts: 21
Joined: Sat Dec 30, 2017 2:27 pm

Re: ST RTC EXTERNAL BETA - WIP

Post by tzok » Sat Jan 13, 2018 9:44 pm

exxos wrote:
Sat Jan 13, 2018 8:48 pm
You can battery backup the keyboard, have seen it done. But is rather power hungry to power the keyboard chip.
That's why I was thinking rather about a pass-through device connected between keyboard and motherboard, that would set the RTC in the keyboard from the modern DS-1307 battery backed-up RTC on this device on power up, and after that be completely transparent or would intercept queries to the original ST RTC and substitute answers from its own RTC. This probably could be done with some ATTiny or similar uC, and it would require no software on the ST side at all.

P.S.
I've found your statement that you've switched to GALs, because TTL IC are now obsolete and hard to buy... really? I see no problem in buying 74HCTxxx chips, while GALs are a real challenge to find, not to mention programmer for them.

User avatar
exxos
Site Admin
Posts: 2575
Joined: Wed Aug 16, 2017 11:19 pm
Location: UK
Contact:

Re: ST RTC EXTERNAL BETA - WIP

Post by exxos » Sat Jan 13, 2018 10:43 pm

tzok wrote:
Sat Jan 13, 2018 9:44 pm
That's why I was thinking rather about a pass-through device connected between keyboard and motherboard, that would set the RTC in the keyboard from the modern DS-1307 battery backed-up RTC on this device on power up, and after that be completely transparent or would intercept queries to the original ST RTC and substitute answers from its own RTC. This probably could be done with some ATTiny or similar uC, and it would require no software on the ST side at all.
It may be best to start a new thread on this as your talking about other solutions.

tzok wrote:
Sat Jan 13, 2018 9:44 pm
I've found your statement that you've switched to GALs, because TTL IC are now obsolete and hard to buy... really? I see no problem in buying 74HCTxxx chips, while GALs are a real challenge to find, not to mention programmer for them.
Normal logic chips are becoming harder to find, and have been for some years. A lot of chips vanished a long time ago, ABT range is very limited now. HCT are still around some, but not good enough for my needs. A lot I brought in the past have been discontinued. GALs are obsolete, I have no problems buying those. Even so I am moving to more modern PLD's which are still in production and faster.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

Post Reply