+OLD CS1 Posted January 30, 2018 Share Posted January 30, 2018 This console I have is thought to be a v2.2, but when I look up the GROM part numbers they appear to be from the original console. I have CD2155ANL, CD2156NL, and CD2157NL. Quote Link to comment Share on other sites More sharing options...
kl99 Posted January 30, 2018 Share Posted January 30, 2018 afaik GROM1 and GROM2 are identical. those are TI BASIC.only GROM0 contains the v2.2 patch where the only difference is that they removed the check for ROM only cartridges. so only one of them should differ. In the 99/8 sourcefiles it can be read that they actually got the approval to re-insert the check for ROM only cartridges, but they didn't have the time to do that yet, at least for the version of the sourcecode that is public. that is why all 99/8 are not compatible with the Third party cartridges. 2 Quote Link to comment Share on other sites More sharing options...
+mizapf Posted January 30, 2018 Share Posted January 30, 2018 afaik GROM1 and GROM2 are identical. those are TI BASIC Yes. If you check the ROM files of MAME, the ti99_4qi.zip only contains one file (994qi_grom0.u29). The other GROMs are inherited from the parent driver ti99_4a. 1 Quote Link to comment Share on other sites More sharing options...
+mizapf Posted January 30, 2018 Share Posted January 30, 2018 that is why all 99/8 are not compatible with the Third party cartridges. I just played Defender on the emulated 99/8, gets listed as [D] FOR DEFENDER. Different stages of development? Quote Link to comment Share on other sites More sharing options...
kl99 Posted January 30, 2018 Share Posted January 30, 2018 (edited) I just played Defender on the emulated 99/8, gets listed as [D] FOR DEFENDER. Different stages of development? And on the emulated 99/4 and 99/4A QI it doesn't show? Edited January 30, 2018 by kl99 Quote Link to comment Share on other sites More sharing options...
+mizapf Posted January 30, 2018 Share Posted January 30, 2018 And on the emulated 99/4 and 99/4A QI it doesn't show? Yes. The 99/8 in MAME is essentially Ciro's 99/8, so maybe he can try. Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted February 2, 2018 Author Share Posted February 2, 2018 So... anyone know what the part number is for the v2.2 GROM0? Quote Link to comment Share on other sites More sharing options...
digdugnate Posted February 2, 2018 Share Posted February 2, 2018 here's a picture of a known QI board- i'm trying to find a specific part number for GROM0. Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted February 2, 2018 Author Share Posted February 2, 2018 Remember: "QI" does not necessarily imply v2.2. I have at least two "QI" boards which are not v2.2. That said, the GROMs are to the right of the CPU and the print is not clear in your pic. Can you do a close-up of them? Quote Link to comment Share on other sites More sharing options...
digdugnate Posted February 2, 2018 Share Posted February 2, 2018 well, rats. i was hoping i would be able to help. It looks like that the GROMs in my pic are the same as what you already have. Quote Link to comment Share on other sites More sharing options...
digdugnate Posted February 2, 2018 Share Posted February 2, 2018 here's something else i found: "D. If most non-TI modules will not run in the console, check the TI titlescreen for a 1983 copyright notice. Iffound, the console contains the TIoperating system which prevented use ofnon-TI modules. This operating systemmay be bypassed with some softwareprograms or aftermarket hardwareadaptors. Replacement of GROM 0 in theconsole (chip number CD2155) with a chipfrom an earlier production console willreplace the newer operating system andpermanently solve the problem." ftp://whtech.com/articles/limanews/CONSOLE.TXT Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted February 2, 2018 Author Share Posted February 2, 2018 So they are both the same part number? I hope that is not the case. Quote Link to comment Share on other sites More sharing options...
digdugnate Posted February 2, 2018 Share Posted February 2, 2018 that's what i've been seeing, without having a 2.2 in front of me. Quote Link to comment Share on other sites More sharing options...
+jedimatt42 Posted February 3, 2018 Share Posted February 3, 2018 The chip I pulled from my v2.2 non QI console was labelled CD2155|8327MCFX|Philippines The other groms have a different style for the second line: MFX 8249 or NFX 8249 Maybe this can be used to determine the vintage... -M@ Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted February 3, 2018 Share Posted February 3, 2018 (edited) There might be two ways to tell: are the older chips CD2155ANL or are they just CD2155NL? The "A" is key, as that usually indicates a revision. The other possibility is in that second line, as that may be the date the code was finalized and the chips were made: 8327= 27th week of 1983, which would be about right for the introduction of the V2.2 consoles. Edited February 3, 2018 by Ksarul 1 Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted February 3, 2018 Author Share Posted February 3, 2018 Ah, then the GROM0 on this board may indeed be a v2.2. When I looked last night at the two display consoles on my shelf they are simply CD2155. Now I just need to get this unit to power up to know for sure. Quote Link to comment Share on other sites More sharing options...
+jedimatt42 Posted February 3, 2018 Share Posted February 3, 2018 My CD2155 from the v2.2 console had no ANL or NL on them. "Simply CD2155" just as OLD CS1 indicates. -M@ Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.