The last piece I as waiting for came in today and the ram card works both mechanically and functionally.
Based on what I learned today I have some final cleanup and updates to do, so don't actually order any of the boards currently on github. (I'm leaving the note at the top saying "do not use yet") But, the board labelled "v003" works with SRAM such as CY62128, the Samtec pin socket, and the "v003-s" 3d printed carrier. It works both with and without the cap & resistors. The cap preserves the ram if you unplug the card while the machine is on, but not if you leave the card inserted and turn the machine off. It must be draining into the machine. I either need to add some form of backfeed protection like at least a diode, or just scrap the whole complication and just have a simple board with just the chip. The machine does not recognize more than 128K ram even with a 256K sram installed and the A17 line connected. And I cannot get both sram and flash footprints on the board at the same time (without making the board bigger to make room for more traces). And I have determined that the cheap ebay/aliexpress pin header isn't usable. So that eliminates several possible alternative options and configurations and complications I can just remove, and be left with a simpler set of directions and parts. So what I'm doing now is tidy up the board to remove the A17 line and the silkscreen text from saying anything about rom or 256k, and this board will just be 128K RAM. And I made a separate ROM version that uses a 39SF020 or 29EE020 etc flash chip in place of the sram, and a programming adapter for the ROM version to program it. That version does need a single resistor for /WE besides the flash chip itself. None of these updates are on github yet but will be shortly. -- bkw On Sat, Oct 10, 2020, 7:02 PM Brian White <[email protected]> wrote: > I'm working on a diy expansion card you'll be able to make yourself. It's > not ready yet but getting close. I'm currently waiting for my latest pcb > version to come in, and a better type of pin header. > > The latest version 3d-printed part has come in and it checks out. > > > http://github.com/bkw777/WP-2_IC_Card > > On Sat, Oct 10, 2020, 6:45 PM <[email protected]> wrote: > >> D. >> >> I also just bought a WP-2 a couple of weeks ago off eBay as well. For >> the battery, I ordered the correct ones (buy lots since like the 100 it is >> how the ram is saved, but I later found out any 3v coin cell will work. If >> its smaller just add some cardboard to fill the space. >> >> As for the extra internal memory, the only way to know is to open it up, >> at least that is what I did. Order a chip, was $6 with shipping off eBay, >> was worth it to just know you have extra memory (1PCS Hitachi HM628128DLP-5 >> HM628128 628128 128K CMOS SRAM DIP32 is the listing on eBay, and can >> confirm it works came fast as well) but it is used just as a ram disk. >> Guess that would be how to check without openning it, if the ram disk is an >> option to save then it has the chip. There's a YouTube video that shows >> how to install I think. >> >> As for the memory cards, I read they are almost impossible to find, with >> the extra internal ram disk they really are not as important. The nice >> thing is after getting batteries and a chip your pretty much set, can use >> the same cassette and cord from the 100 as well, and the power cord as well. >> >> Fun little machine, and nice that it has true spell checking. >> >> Here's a few links with the manual and some other good info: >> >> >> https://munk.org/typecast/2020/09/09/tandy-wp-2-user-manual-happy-septandy/ >> >> http://fervor.net/index.php/tag/tandy-wp-2/ >> >> http://www.bitchin100.com/wiki/index.php?title=Tandy_WP-2_DocGarden >> >> Enjoy, >> Mark >> >> >> >> On Oct 10, 2020 5:48 PM, dano none <[email protected]> wrote: >> >> >> >> Hi All, >> >> >> I purchased a wp-2 off of ebay. One of the nice things about buying a >> wp-2, is you can justify the use of space, by just telling yourself.. >> >> All I have to do, is get rid of one hard back book! =) >> >> >> >> Assuming a sympathetic audience on the 100 mailing list I have some >> questions, I've not seen answered on the club 100 site, or I don't know >> where to look. >> >> >> When I received the unit, the 2430 backup battery was dead. I've >> ordered one, but it will take a week, and stopping by my local Radio Shack >> (tm) isn't an option. I do have a low battery backup indicator and the >> screen flashes, which makes trying to use it really annoying. >> >> >> 1) How does one check to see if the extra ram is installed? >> >> a) If no extra ram is installed, does this take a standard ram >> chip? >> >> >> 2) There is a space on the side of a memory card. >> >> a) Is this some sort of special memory pin out or something more >> common like PCMCIA? >> >> >> Thanks, >> >> d. >> >> >>
