My new $10 CoCo system showed up today 
Its a 16K 1.1Rom system. Was mint in the orig box.. doesnt look like it got very much use. And unlike my CoCo2 this one likes the sound of its own voice I have a working tape system again.
I have one question…
I have a spare CoCo 2 board with bad ram. It has extended Color basic. Can I take the 2nd rom chip out of a CoCo2 board and put it in a CoCo1?
My new coco1 is a gray USA made 26-3004A. Center sticker.
Thanks!
This post was submitted by broke_coco.
Well to reply to my own post.. The answer is yes. A CoCo2 extended color rom seems to work in a CoCo1. I decided to brake the warrenty sticker and just give it a shot.
Lol.
I was going to mention you can just replace the basic rom with the extended basic version. But you beat me to a reply. Have fun playing around with it.
laters
Briza
Sounds like an F board. Should be easy to upgrade to 64K, if you’ve got the RAM lying around (if not, I do between eBay and digging up some old XT boards where 256K or 512K was made up of many banks of 4164s – and since they used partiy, there are even more chips – a whole extra bank in 512k). Hmm…does anybody know if you could use 41256s in place of 4164s (ie same pin count and pinout)? I know by switching a couple of pins around you can use 4164s in place of 4116s – apparenly common practice on Williams arcade machines these days. (Though I probably still have more 4164s than 41256s.)
@Briza – How? IIRC, it required both ROMs to have Extended BASIC, and we’re talking about the 24-pin Moto ROMs here. Or were you referring to adapting a 27xxx chip to match 6876x pinout?
@broke_coco – I almost hate when I get one with the warranty seal intact. They’re so rare I hate to break it. I have an FD-500 (original box, packing etc.) that reads but won’t write and the warranty seal is intact.
Question: How can one call equipment that is well over 20 years old no matter if in mint condition as new?
@dentman42, I know the feeling. I recently bought an original 16K CoCo serial #175 with the sticker intact. I think it needs fixing but I hate to crack open the case.
PunkMaister: NEW to ME
Dentman42: I have a 4164s.. I think I have a few original XT mobo’s and a ton of ISA ram cards.
Do I just pop them in and change the jumpers on the CoCo motherboard? I saw jumpers that said “16K” and “64K”
I didnt remove the big metal cover when i was in there so i dont know if there are empty sockets or what…
For the Extended CB there was an empty socket on the motherboard. I just removed the one ECB rom from my parts CoCo2 motherboard and popped it in there. Turned the CoCo1 on and was greeted with the ECB boot screen. I didnt swap the CB roms.. My CoCo1 cam with 1.1.
Thanks!
To upgrade an ‘F’ board to 64K, you do the following:
Remove capacitors C58, C60, C62, C64, C66, C68, C70, and C72.
Set the jumper to the left of R69 to the 64K position.
Set the two jumpers to the left of U21 to the 64K position.
Jumper the two staking pins above R42 to 64K.
Install 64K RAM chips (4164) in U21-U28.
To determine that you have an ‘F’ board, look for a number ening in 285 printed on the board near the power supply.
CoCo 1′s were usually SCB 1.1 and ECB 1.0. CoCo 2′s were SCB 1.2 and ECB 1.1 iirc.
I always forget about cutting the caps because I did that on my first CoCo before I ever got 64k – just to make high speed mode more stable. Didn’t notice any increase in RFI either.
Be glad it’s an F board. My first was an E and required bending up pins and soldering jumper wires in addition to moving the jumpers.
@Punkmaister – if it’s in like new condition, it’s like new no matter how old it is. I just got a TI-99/4a last month that I’d call like new. I’m not sure it had ever even been hooked up – the cords didn’t look like they’d ever been unwrapped and there wasn’t a mark on the computer. It looked like somebody had taken it out of the plastic to look at it and put it right back. The box had some shelf wear (I’ve seen worse on store shelves) but the contents look new. The CF adapter for the TI crowd is only about 40 bucks and adds 32k RAM and a parallel port, but doesn’t come with any kind of case, just a circuit board. Talk about a wasted system – full 16 bit processor but TI was so convinced that they could sell you stuff to unlock the abilities later that it’s pretty well crippled out of the box. You at least need the Extended BASIC cartridge to do anything with it (standard TI BASIC makes Color BASIC look incredible – it can’t even access the RAM expansion) and some of the ML programs need the editor/assmebler cartridge to run them.
DarrenA,
Thanks! Thats good info to have. I looked around and I have tons of 4164′s to pick from. I’ll verify what board I have and put your instructions aside with a set of ram chips. Since my original CoCo2 is back in action(see my other thread) Im not in a big rush to start cutting caps and such.. If I find a aftermarket keyboard i’ll do the upgrade…this chicklet keyboard is “interesting” but I cant see my self spending much time on this machine. Here’s the ebay pic of my $10 coco1: http://cralt.com/coco1.jpg
dentman, I’ll see if my parts CoCo2 mobo has SCB 1.1 or 1.2.. Thats good info to have. This CoCo1 came with a notice about a 1.0 to 1.1 upgrade in the paperwork that was done after manufacture but before purchase.
@DarrenA – Thanks for the info on the caps. I had that at one time, but haven’t been able to find it again. Now I should be able to upgrade my F board CoCo1.