_The Doctor__ Posted May 23, 2020 Share Posted May 23, 2020 (edited) Yes on the reversal I am looking at the currents they provide... Edited May 23, 2020 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 23, 2020 Author Share Posted May 23, 2020 On 5/14/2020 at 10:17 AM, mytek said: The BC547 should be fine as a substitute (showed as a cross for the 2N3904 which is very similar to the PN2222 that I spec). This mystery is getting very perplexing, although good find on pulling U25 (74F138) to get things working, so we at least know the general area of the problem (the IDE section). Looking a bit closer, the only way that a shorted transistor or diode would be an issue is if they were both shorted or if the /$Cx_RD signal coming out of pin 10 on the 74F138 chip was permanently selected. this doesn't seem likely after you swapped in the HCT138 which was known to work in it's other location. Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 23, 2020 Author Share Posted May 23, 2020 The board has the same issues with the original pn2222, a used 2n3904 and the current bc547 anyway. Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted May 23, 2020 Share Posted May 23, 2020 That may be as it is similar, but it can't hurt to swap q2 and q6.... the reason I say this is some spec differences... it can't hurt. as you know which way they need to be oriented. Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted May 23, 2020 Share Posted May 23, 2020 (edited) was the original defective? I don't know... Your DMM might have a test function... I was hoping you had the exact parts and could swap a known good one in there. I've already received defects from china before... so it's just a suggestion... q2 for q6 and if the problem resolved great, if it moved/changed you'd know that as well Edited May 23, 2020 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
Simply_Graham Posted May 23, 2020 Share Posted May 23, 2020 (edited) For Q6 the current,Voltage and Hfe specs arn't that stressed as it's used as a logic switch so hard on or off as 5V and very Low current. That of course is only for this specific use as Q6. And of course not to have failed (usually short circuit I've found) Edited May 23, 2020 by Simply_Graham Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted May 23, 2020 Share Posted May 23, 2020 (edited) somethings stressed / starved with voltages of 4.1, 4.3 etc. Edited May 23, 2020 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 23, 2020 Author Share Posted May 23, 2020 Looks like there are 5 ic's not shared with my XEL. Going to re-order those, and might as well throw in some pn2222's while i'm at it. Quote Link to comment Share on other sites More sharing options...
Simply_Graham Posted May 23, 2020 Share Posted May 23, 2020 In regard 'Stressed' refering to the Q6 Transistor. not the low voltage levels 1 Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 24, 2020 Author Share Posted May 24, 2020 While in the ordering mood, I ordered the Dreamblaster module and a U1mb from TBA. The U1mb is to replace the one I stole out of my 800xl for the xld. I'll leave the original black Candle board in the xld. 1 Quote Link to comment Share on other sites More sharing options...
+Stephen Posted May 24, 2020 Share Posted May 24, 2020 55 minutes ago, chevymad said: While in the ordering mood, I ordered the Dreamblaster module and a U1mb from TBA. The U1mb is to replace the one I stole out of my 800xl for the xld. I'll leave the original black Candle board in the xld. Dreamblaster is a fun little device, killer sound. 1 Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 24, 2020 Author Share Posted May 24, 2020 Experimenting with Midi was one of the main reasons for building an xld. The CF card will be fun to experiment with too, but my nuxx has always done almost everything i've wanted. The new Sophia now has me rethinking video. I'll probably stick to plan though and move the vbxe to the xld and use the internal gbs mods.. allready have them. But maybe the XEL will get a sophia 2.. then it'll be a big debate over which one to use! I'm hopeful one of the ic's I ordered will fix my problems. It's hard to believe it's anything board or solder related since both builds had the same issue. Quote Link to comment Share on other sites More sharing options...
Simply_Graham Posted May 30, 2020 Share Posted May 30, 2020 Any News, or still waiting on parts? Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 30, 2020 Author Share Posted May 30, 2020 No parts yet. Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 30, 2020 Author Share Posted May 30, 2020 Parts came in the mail today.. Success!! It was NOT any of the IC's. It was NOT Q2-Q5. It WAS in fact Q6 as the Doctor suspected. Evidently the original Pn2222a was trash to begin with. Then the 2n3904 I tried first didn't work, nor the 3 different brand new bc547's. But a brand new PN2222a installed today and everythings groovy. That has to be the world's most expensive transistor!! Lol But hey, I got me a new oscilloscope out of the deal. If I hadn't delaminated part of the old board around the PIA i'd build that one too. If anyone should need a pair of IO boards I have a pair of black boards unused. Thank you everyone for putting up with me. It was at times extremely frustrating, but with my shop packed away in storage and covid, I'm not sure what else I'd be doing anyway. Now to build my GBS adapter board and move my vbxe from the xel into this machine. Looks like the xel might get a sophia 2. Only 1 of my 2 CF cards apparently works, but hey, it does work and the light turns green now! One last thing, i've got the dreamblaster board installed now. Is the machine supposed to play the "have you played atari today" tune? It doesn't, i'm not sure if it's supposed to, and totally unsure of settings in either case. 3 1 Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 30, 2020 Author Share Posted May 30, 2020 Something else interesting. The first 4 PN2222a transistors (Q2-5) I had on hand when I started on the board. I needed one more, which I ordered from Digikey, that ended up being Q6. Kinda coincidental..... Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted May 30, 2020 Share Posted May 30, 2020 Congrats to @chevymad on getting your machine working but it's worth pointing out that Michael suggested this a couple weeks ago. Probably not that surprising since he designed this thing! On 5/13/2020 at 3:23 PM, mytek said: Check D14 and Q6. Because if U25 wasn't bad, then likely something is wrong with those components, or one of them is in backwards. They connect to data lines D6 an D7 and are used to convey both an IDE device signature, and the swap latch state. Specifically I suspect Q6 to be the problem if it's not the 74F138. Anyway, congrats again! Now have a beer and enjoy your success. 1 Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 31, 2020 Author Share Posted May 31, 2020 (edited) You'll notice that it was after that post, that I tried the other transistors I had on hand. And Michael felt that they should have worked. There is however, enough different between them to cause problems evidently because both 2n3904 and bc547's have the same issue as the "bad" pn2222a I started with. " On 5/14/2020 at 10:17 AM, mytek said: The BC547 should be fine as a substitute (showed as a cross for the 2N3904 which is very similar to the PN2222 that I spec). " That's just to say, his suggestion wasn't ignored. I had some transistors on hand we thought would work. They do not. Edited May 31, 2020 by chevymad Quote Link to comment Share on other sites More sharing options...
Simply_Graham Posted May 31, 2020 Share Posted May 31, 2020 It's great that another XLD is up and working. The S2 requires that the MIDI MCU be programmed and that the two jumpers on J3 pins 3 to 4 & 6 to 7 be shorted with a jumper block, assuming you don't use the external MIDI connectors, I was playing so may only need 6 to 7 to enable. Works completly independantly of the Main Atari computer. Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted May 31, 2020 Share Posted May 31, 2020 (edited) 5 hours ago, Simply_Graham said: The S2 requires that the MIDI MCU be programmed and that the two jumpers on J3 pins 3 to 4 & 6 to 7 be shorted with a jumper block, assuming you don't use the external MIDI connectors, I was playing so may only need 6 to 7 to enable. J3 is only 6 pins. Per the schematics and the board silkscreening, pins 3-4 need to be shorted if you don’t have DIN connectors installed. If you intend on completing the spec I/O boards with DIN connector and MIDI source clock selector switch, no jumper is required. EDIT: Correction; the Beta version of J3 had 6 pins; the final production design has a 7-pin header here. Edited May 31, 2020 by DrVenkman Corrected Misstatement Quote Link to comment Share on other sites More sharing options...
Simply_Graham Posted May 31, 2020 Share Posted May 31, 2020 (edited) Deleted and reposted using the 'Quote' option Edited May 31, 2020 by Simply_Graham Deleted Quote Link to comment Share on other sites More sharing options...
Simply_Graham Posted May 31, 2020 Share Posted May 31, 2020 (edited) 4 hours ago, Simply_Graham said: pins 3 to 4 & 6 to 7 be shorted with a jumper block, assuming you don't use the external MIDI connectors, I was playing so may only need 6 to 7 to enable. That's very strange as both the Silk screen and Schematic on the versions I have released 27-4-2020 Show it as being 7 pins. To Enable MIDI short pins 6&7 as previously stated As Dr Venkman mentions 3&4 to be shorted if you dont have the additional board connected with the MIDI connectors. It may not me perfect English but please check this quote above Edited May 31, 2020 by Simply_Graham Added Screengrab Quote Link to comment Share on other sites More sharing options...
chevymad Posted May 31, 2020 Author Share Posted May 31, 2020 Ya, it's 7 pins now. I'd noticed the change earlier from the first version boards. Been poring over pics of everyone's XLD's for awhile now LOL. Also ran into a change on the gbs2vga board and bom last night. The BOM i'd used to order parts and the board I just got from Dropcheck didn't agree. Inductors swapped positions and a couple more resistors added. As these things get refined stuff is changing. So since I have the Midi IO board connected, I don't need any jumpers? And it IS supposed to play the tune correct? Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted May 31, 2020 Share Posted May 31, 2020 1 hour ago, Simply_Graham said: That's very strange as both the Silk screen and Schematic on the versions I have released 27-4-2020 Show it as being 7 pins. Apologies, you are correct. That was changed from the Beta board and schematic that we built before the design was released publicly. The earlier version of the schematic (and the boards themselves) have only 6-pins at J3. Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted May 31, 2020 Share Posted May 31, 2020 33 minutes ago, chevymad said: So since I have the Midi IO board connected, I don't need any jumpers? And it IS supposed to play the tune correct? If you have the I/O board built and connected, and if you have the MIDI Source switch set to Internal and your MIDI PIC chip programmed, you'll get a jingle as the system powers on. For the production design, you should jumper pins 6-7 to enable MIDI, per the final schematic note and as @Simply_Graham states above. 1 Quote Link to comment Share on other sites More sharing options...
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