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Re: The TF330 is here
Posted: 27 Nov 2018 20:09
by terriblefire
Maybe next time... you can waste a lot of time with this sort of thing.
Ok it’s now time to do something sad... this guy isn’t cutting it anymore. He’s a MC68030RC16...
9871BD07-280D-40E4-AD54-6265CBD42703.jpeg
He needs replaced..
I have to solder one of these into this board perm....
And the plastic versions don’t fit due to the standoff’s.
0DB0E120-1BA9-44D7-A4B7-2B5CB62C8AE8.jpeg
I await the hate
Re: The TF330 is here
Posted: 28 Nov 2018 08:01
by 8 Bit Dreams
For me would be easier to redesign that pcb, making 4 holes larger instead of sacrifice ceramic cpu - these are getting rare...
Re: The TF330 is here
Posted: 28 Nov 2018 08:03
by terriblefire
The cost would be the same for me and would delay the TF330 until after Xmas
Re: The TF330 is here
Posted: 02 Dec 2018 00:37
by terriblefire
Update.
I have SDRAM working well enough to run code and games in. I havent turned on caches yet.
The CIA issue is still present. I can reproduce this reliably and it seems to be the cause of all my problems right now.
Essentially randomly a CIA write doesnt happen. Its very odd. This test code from DiagROM can reproduce my issue reliably.
Code: Select all
.loopa:
move.l #$f0,$dff180
move.b $400(a5),CIACtrl-V+1(a6)
move.b $500(a5),CIACtrl-V+2(a6)
move.b #(CIATIME&$FF),$400(a5)
move.b #(CIATIME>>8),$500(a5) ; Set registers to wait for 10000ms
.wait:
move.w #$0,$dff180
cmp.w #120,Frames-V(a6)
bge .vblankoverrun
btst d2,$d00(a4)
beq .wait
add.l #1,Ticks-V(a6)
move.w #$f,$dff180
.no:
dbf d6,.loopa ; Repeat this so we are doing it for a while
bset #0,(a3)
clr.l d6 ; Clear D6, meaning we have executed this without Vblank overrun
bra .exit
Essentially the traces show that after a few turns round the loop the write to CIA timer B doesnt happen/take and we never get a reply from BFED01.
Very odd. Nothing unusual on the scope. The cycles are longer than the standard ones. Probably some emulation for the CIAs going on in the chipset.
EDIT: I have attached the trace. The line that seems to be having an issue is
2287 00BFE601 HIGH BYTE AEAE HIGH BYTE 1 0
listing.txt
Re: The TF330 is here
Posted: 02 Dec 2018 12:42
by terriblefire
Some interesting behaviour observed.
If you do not DSACK the CIA cycles then they repeat over and over.... At a guess if they arent acknowledged before a certain time in the DSACK cycle then the write is ignored (reads dont really matter because the data is on the data bus all the time).
I get this when using the 020 at 14Mhz
020_cia.JPG
And this when doing the same thing crossing the clock domains at 50Mhz..
030_cia_fail.JPG
Notice how little overlap there is between AS20 being high and DSACK being low in the 030 cycle. I think this is possibly the issue?
Re: The TF330 is here
Posted: 02 Dec 2018 13:12
by terriblefire
So if you miss the window completely you dont register a write. just did this artificially as a test..
miss_the_window.JPG
Which results in a completely repeatable/reliable never getting any results.
miss_the_window2.JPG
Very interesting that the chips behave this way actually.
Re: The TF330 is here
Posted: 02 Dec 2018 14:25
by terriblefire
Ok so a simple clock switch for these cycles works a treat but seems to have the same timing (to me) gaps as the others. Its a bit wasteful of CPLD space to do this.
030_cia_speed_switch.JPG
It is however 100% reliable.
Re: The TF330 is here
Posted: 02 Dec 2018 17:46
by 8 Bit Dreams
If You are running out if space on cpld You can take XC95288XL - these are pin compatible with XC95144XL...
That would be even better, cause i can get these cheaper than XC95144XL's.... :)
Re: The TF330 is here
Posted: 02 Dec 2018 17:49
by terriblefire
8 Bit Dreams wrote: 02 Dec 2018 17:46
If You are running out if space on cpld You can take XC95288XL - these are pin compatible with XC95144XL...
That would be even better, cause i can get these cheaper than XC95144XL's.... :)
Please tell me where already :)
Re: The TF330 is here
Posted: 02 Dec 2018 19:08
by 8 Bit Dreams
terriblefire wrote: 02 Dec 2018 17:49
Please tell me where already :)
Please don't laugh...on Ebay... :oops: :oops: :oops: