What is the Peripheral Expansion System about? (warning lots of questions)

[Major_Tom_coming_home]

I'm a newbie to the TI/99 and have a few questions about the Peripheral Expansion System. I'm very curious and Hopefully this isn't too much at once

 

1. Back when the TI-99 was current generation, what was the purpose and usefulness of the Peripheral Expansion System? Would it allow the TI/99 to have functionality that was otherwise impossible, or did it just eliminate the need for sidecars and stand alone peripherals?

 

2. Was there any software that required more than one sidecar expansion, or was it a case of the TI/99 being discontinued before the Peripheral Expansion System had any purpose other than convenience and aesthetics.

 

3. In the present, is there anything the Peripheral Expansion System does that can't be replicated by modern homebrew add-ons or is it something mainly used only by collectors and people who prefer using original hardware as much as possible?

[+arcadeshopper]

1: it allowed for expansion including ram, rs232/pio ports, floppy disks, hard drives, ram disks, languages (UCSD pascal) cpm/coprocessors, SID sound card, FORTI sound card, GRAM emulators etc.. sidecars did some of these but not all and they took up a 6foot desk..

 

2: many programs require a 32k ram sidecar and a disk controller sidecar, and a rs232 sidecar..that just made your TI 3ft wider..

 

3: there are sidecar devices called nanopeb or cf7 for ram, floppy disk emulation and rs232 pio ports, though they are not always available he sells a few then wanders off then sells a few..

The 32k expansion has been available for a while on a standalone sidecar and sold at arcadeshopper.com. Sold a bunch of them and also sell kits..

back in the "old" days there was a corcomp micro expansion that put floppy, 32k ram and rs232/pio on a sidecar.. these were great, but are seldom available and sell for hundreds when they pop up on ebay.

No sidecars are available for: SAMS memory, Myarc memory, Pcode, CP/M, Ram disks, hard disk controllers, video enhancement, cpu replacement, SID sound card, FORTI sound card..

 

mainbyte.com has great pictures and info on the stuff available for the 4/a up to recently. He doesn't have a lot of the new stuff.. but lots of cards and perepherials there with details

 

Greg

Edited May 17, 2017 by arcadeshopper

[+arcadeshopper]

[+arcadeshopper]

new 32k sidecars: https://www.arcadeshopper.com/wp/?page_id=11#!/32k-sidecar-memory-expansion/p/73789245/category=22255086

and case: https://www.arcadeshopper.com/wp/?page_id=11#!/3D-printed-case-for-32k-Sidecar/p/80201707/category=22255086

 

nanopeb/cf7: http://webpages.charter.net/nanopeb/

[PeBo]

You could also insert a fully operational computer on a card.

 

Called the Geneve 9640, it included a cartridge saver that would allow cartridges to be saved to disk, 640 K of 16 bit RAM, a 12 MHZ processor , 80 column display 512x424 graphics w/256 colour, an IBM XT keyboard, MDOS and "Advanced BASIC" and other niceties.

 

So yes, you could use the PEB to expand your /4A, or use ot to provide you with a brand new computer!

 

How cool is that?

[Stuart]

 

Called the Geneve 9640, it included a cartridge saver that would allow cartridges to be saved to disk, 640 K of 16 bit RAM, a 12 MHZ processor , 80 column display 512x424 graphics w/256 colour, an IBM XT keyboard, MDOS and "Advanced BASIC" and other niceties.

 

 

[Pedantic mode on!]

 

It's actually a 3 MHz processor, same speed (but more efficient) than the TMS9900. The 12 MHz crystal is internally divided to produce a 4-phase, 3 MHz clock.

 

[Pedantic mode off!]

[+arcadeshopper]

plus.. how cool is this.. and blinky lights are the best part

[x24b]

Why did I buy a PEB box way back when?

I wanted to save files on Floppy Disks and use an MX dot-matrix printer to print out my Extended Basic source code, business bills/papers, 99er Club News, college homework and get 'up-to-date' technical computer information on far-away dial-up BBS's.

 

I obtained a PEB box with an RS232 card so I could dial-up on a POT's (Plain Old Telephone) land-line at home with my Modem to connect to BBS's (Bulletin Board Service).

I used the TI Terminal Emulator II cartridge and speech synthesizer to have my computer 'speak the text' on a BBS while I did other things, like build model airplanes.

The TI Terminal Emulator II cartridge is used to control how the 99/4A talks with other computers using a Modem, with an added ability to speak the text files you download.

People would upload articles, tips, source code, news, sports, and politics in plain ASCII Text files to these Servers. You could peruse just the files (then up or download them) or read the text-only scroll provided/edited by the BBS owner.

Just before BBS's died, due to the early Internet, they started "ASCII Art" as well. There was some AMAZING art made.

 

Some guys would have a dedicated computer (I think I remember Apples, PC's and even 1 or 2 TI's) running BBS software in their home, and paid for a dedicated land-line (some had MANY!) waiting for people to dial. You could upload and download files from the BBS.

I remember getting a $300 phone bill one month because of this "Hobby"! Back then you had to pay extra for Long-Distance phone calls. One of my favorites was in New York. I lived in CA.

Many weekends and after work hours were spent doing it.

 

https://en.wikipedia.org/wiki/List_of_BBS_software

[apersson850]

 

[Pedantic mode on!]

 

It's actually a 3 MHz processor, same speed (but more efficient) than the TMS9900. The 12 MHz crystal is internally divided to produce a 4-phase, 3 MHz clock.

 

[Pedantic mode off!]

True. One reason for the higher efficiency of the TMS 9995 is that it has one stage instruction pipelining. If I remember correctly, it also gets away with the read before write memory access implementation. It's not necessary with a byte-addressable CPU with a byte wide data bus. But it is on a byte-addressable CPU with word wide bus.

[+mizapf]

I had no look inside the 9995, I know that the input clock is 12 MHz, the output clock is 3 MHz (div by 4), but I don't know where the clock is divided. Is it available to the microprograms? I would almost guess so, because the 9995 requires so much fewer cycles than the 9900 that it seems unlikely (as I said, I don't know for sure) how you can possibly get there if there were no subcycles. It is not just the missing read-before-write.

[Sinphaltimus]

I originally got a PEB last year so I could take save programs to disk instead of tape and take advantage of the 32k memory expansin (the side cart was not yet ready).
I ended up (through luck) getting 2 PEBs, one was in near mint condition - I left that in the box and do not use it. I hope to someday have it fully populated.
The more beat up one I modded so I can use a GoTek and 3.5" floppy in it. Replaced fan and PSU with ATX versions, installed temp probes since I opt'ed not to change out my voltage regulators.
I hope to someday fully populate this as well, possibly with newer PEB cards should any come out.


Something about owning these keeps me warm and fuzzy inside.

[x24b]

I originally got a PEB last year so I could take save programs to disk instead of tape and take advantage of the 32k memory expansin (the side cart was not yet ready).

I ended up (through luck) getting 2 PEBs, one was in near mint condition - I left that in the box and do not use it. I hope to someday have it fully populated.

The more beat up one I modded so I can use a GoTek and 3.5" floppy in it. Replaced fan and PSU with ATX versions, installed temp probes since I opt'ed not to change out my voltage regulators.

I hope to someday fully populate this as well, possibly with newer PEB cards should any come out.

 

 

Something about owning these keeps me warm and fuzzy inside.

 

There must be a list of all PEB boards that were made and what they were for. Anyone have a link? Just dreaming here.

[digdugnate]

I got a PEB primarily for the disk drive and 32k expansion- plus it adds to the 'authentic' look that appeals to me for the hobby. I like being able to have the 'real thing' on my desk and using it!

[apersson850]

It's not the crystal itself that's interesting, it's how the CPU runs internally. The 99/4A has a 48 MHz crystal inside for the CPU, but that's just to be able to generate all the phases of the main 3 MHz clock.

[PeBo]

I got a PEB primarily for the disk drive and 32k expansion- plus it adds to the 'authentic' look that appeals to me for the hobby. I like being able to have the 'real thing' on my desk and using it!

 

That's why I bought one in the 80's (plus getting an RS232 so I could hook up a modem). Spent the full amount of an inheritance from my grandmother ($1000 (that's the equivalent of $2, 445.81 in 2017 dollars!)) to get it too!

 

In the name of full disclosure though, while I DO still use it for particular applications, generally it has become a very sexy (and heavy) monitor stand that gets powered up maybe 5% of the time that I power up the console.

 

But even though most of it's functions have now been replicated by alternative modern devices, you are absolutely right....because I had one the first time around, my 4A would just look naked without one!

[matthew180]

True. One reason for the higher efficiency of the TMS 9995 is that it has one stage instruction pipelining. If I remember correctly, it also gets away with the read before write memory access implementation. It's not necessary with a byte-addressable CPU with a byte wide data bus. But it is on a byte-addressable CPU with word wide bus.

Correct, the 9995 does not need the read-before-write because it has a byte-oriented data bus. This has an advantage only for byte writes.

 

I had no look inside the 9995, I know that the input clock is 12 MHz, the output clock is 3 MHz (div by 4), but I don't know where the clock is divided. Is it available to the microprograms? I would almost guess so, because the 9995 requires so much fewer cycles than the 9900 that it seems unlikely (as I said, I don't know for sure) how you can possibly get there if there were no subcycles. It is not just the missing read-before-write.

The input clock is divided inside the 9995 to provide clock phases to drive the internal state. Certain operations will happen at different times, e.g. gating value to the ALU, latching data from the bus to an internal registers (not a CPU register), latching an address to the MAR (memory address register) for memory operations, etc. If you look at the datasheet you will see that a memory operation takes one cycle of the output clock, which is 1/4 of the input. In the 9900, memory operations always happened during the phase2 clock transition, and I suspect the 9995 is very similar, i.e. a memory op is probably always controlled by phase1 or phase2 internally.

 

Regardless, the 9900 and 9995 run at the same internal clock rate, which is 3MHz, and a memory cycle is always at least one 3MHz cycle.

 

The 9995's biggest advantages are the prefetch cycles, and apparently more efficient microcode. It is interesting to note that a normal memory cycle on the 9900 is actually two phase2 clocks, which is 666ns. On the 9995 a memory cycle is one output clock, or 333ns. So it looks like the internal optimizations allow the 9995 to access memory twice as fast as the 9900, which means for word (16-bit) reads and writes it is a level playing field. And for byte reads and writes the 9995 would be twice as fast.

 

OP: Sorry this is totally off topic.

[+helocast]

There must be a list of all PEB boards that were made and what they were for. Anyone have a link? Just dreaming here.

http://www.mainbyte.com/ti99/hardware/peb/ti_cards.html

http://www.mainbyte.com/ti99/hardware/peb/3rd_cards.html

[digdugnate]

 

That's why I bought one in the 80's (plus getting an RS232 so I could hook up a modem). Spent the full amount of an inheritance from my grandmother ($1000 (that's the equivalent of $2, 445.81 in 2017 dollars!)) to get it too!

 

In the name of full disclosure though, while I DO still use it for particular applications, generally it has become a very sexy (and heavy) monitor stand that gets powered up maybe 5% of the time that I power up the console.

 

But even though most of it's functions have now been replicated by alternative modern devices, you are absolutely right....because I had one the first time around, my 4A would just look naked without one!

I almost feel kind bad if I don't fire it up with my trusty TI! It is undoubtedly a very sexy monitor stand. I'd use my Tunnels of Doom disks and TI LOGO just to give me an excuse to use it.

 

my acquisitions have slowed for a few weeks due to upcoming stuff and some recent doc visits (plus for some reason the kids keep growing and needing clothes and food and stuff. the nerve!), but i'm hoping to chase down the Funware carts/MBX carts as part of my next bit of TI stuff.

[PeBo]

Getting my first PEB was a pivotal moment for my computer hobby back then...I went from a base console and a cassette recorder, to dual drives, 32k memory expansion and an RS232 (giving me printing and BBSing capabilities)!!

 

And if having the extra 32K wasn;t enough, after months of using cassettes, my first floppy disc experience was a real "WOW!" moment. I remember thinking that I had just turned my 4A into a 'real' computer!

 

Of course 2 years later we were all using GUI's, hard drives and 512k was the low end of memory! ZOOOOOOOOOOOOOOOOOOOM! and I'm an old fart!

[rickneff68]

Like pretty much everyone else, I got the PEB pretty soon after getting my own TI-99/4A console back in the 80s for the 32 Kb and disk controller/drives. I added 2 RS232 cards and the P-Code card in mine. At the time, I couldn't imagine NOT having the PEB if you wanted to do something other than play games. Like the Speech Synthesizer, it was just something I needed to have to complete the system.

 

Today, however, I don't use it as much since the NanoPEB does most of what I use on a regular basis. (Plus, the TI isn't my computer for productivity anymore.) That said, like my original console, you'd have to pry it from my cold, dead hands!

Edited May 20, 2017 by rickneff68

[apersson850]

Correct, the 9995 does not need the read-before-write because it has a byte-oriented data bus. This has an advantage only for byte writes.

No, because to keep the internal structure of memory accesses with the TMS 9900 as simple as possible, memory access is done the same for byte and word operands. So there's a read before write for word operands too. This is the reason for the TI 99/4A never having autoincrementing memory mapped I/O at the same address for reading as for writing.

The TMS 9995 also has internal memory on a 16-bit bus. This is equivalent to the RAM pad in the 99/4A. The internal memory is typically used for workspace and other frequently used parts of code and data.

Edited May 20, 2017 by apersson850

[+Ksarul]

The lists at Mainbyte cover some of what is out there for the PEB, but there are dozens of cards that aren't included. I started documenting all of the cards I know of in Ninerpedia, but the list thee still has an awful lot of TODOs in it--and the Ninerpedia structure changed somewhat between then and now, which made my method of documentation a bit less useful. To give you an idea of the wealth of PEB cards out there, I have at least 60 different PEB cards. Some of those are obvious, like 32K memory cards from TI, CorComp, Myarc, Captain's Wheel, ICS, and Atronic, but others are a bit harder to pigeon-hole (like the FORTI sound card, the IEEE-488 card, the TMB EPROM Burner, or the SID Master).

[x24b]

http://www.mainbyte.com/ti99/hardware/peb/ti_cards.html

http://www.mainbyte.com/ti99/hardware/peb/3rd_cards.html

Thank you.