Search found 110 matches

by Ped7g
Thu Feb 07, 2019 6:45 pm
Forum: Software
Topic: How to detect that DMA transfer is finished
Replies: 14
Views: 2279

Re: How to detect that DMA transfer is finished

Hm... with interrupts you have to decide on the priorities and what happens when there are two in parallel. The DMA inhibits interrupts, so in burst mode producing audio it may make interrupt stumble by couple of cycles (the memory read is 2T when DMA is configured to fastest mode ... if ZXNDMA oper...
by Ped7g
Thu Feb 07, 2019 1:56 pm
Forum: General
Topic: Wanted: a good IDE for Next Basic dev in Windows
Replies: 9
Views: 2037

Re: Wanted: a good IDE for Next Basic dev in Windows

You have enough reasons to wait until the compilation does finish... :D
by Ped7g
Thu Feb 07, 2019 7:33 am
Forum: Software
Topic: How to detect that DMA transfer is finished
Replies: 14
Views: 2279

Re: How to detect that DMA transfer is finished

On original Z80DMA any write into DMA registers will stop current transfer (but it hadn't burst mode like ZXNDMA, so I'm not 100% sure if it does apply). You can stop the DMA by sending a DISABLE_DMA command. Then you could read the registers to find out where the DMA is so that you could restart i...
by Ped7g
Tue Feb 05, 2019 9:58 pm
Forum: General
Topic: Wanted: a good IDE for Next Basic dev in Windows
Replies: 9
Views: 2037

Re: Wanted: a good IDE for Next Basic dev in Windows

I think there will be multiple tools for Next available, some leaning more toward windows, some more toward being portable... (I personally have only linux machines at home, so my preference is obvious)... and I don't think there will be single "go to" package suited for everyone, as people prefer d...
by Ped7g
Tue Feb 05, 2019 8:42 pm
Forum: Software
Topic: How to detect that DMA transfer is finished
Replies: 14
Views: 2279

Re: How to detect that DMA transfer is finished

If DMA is used in burst mode for audio for example. Is it possible to interrupt DMA in order to to use DMA for byte block transfer (continuous mode) and then continue to use DMA in burst mode for audio? On original Z80DMA any write into DMA registers will stop current transfer (but it hadn't burst ...
by Ped7g
Sat Feb 02, 2019 10:56 am
Forum: General
Topic: Can joystick setting of JS-port 1 or 2 be read from software?
Replies: 3
Views: 699

Re: Can joystick setting of JS-port 1 or 2 be read from software?

Theoretically yes, the NextRegister 0x05 should contain the info ( https://www.specnext.com/tbblue-io-port-system/ ). In BASIC it would be something along: OUT 9275,5 (selecting NextReg 05 on I/O ports), x = IN 9531 (reads value) I can't recall enough of BASIC syntax to show full working example, al...
by Ped7g
Fri Feb 01, 2019 8:07 am
Forum: News
Topic: leaked pic
Replies: 10
Views: 2992

Re: leaked pic

Somehow I never noticed that SQL and CIRCLE are the same key :) This must really be the best looking spectrum yet! Thanks for the update! Do you mean SQR :) I did indeed! I bet you can't guess the sort of thing I was debugging today :) Machine-learning neural-networks optical-character-recognition ...
by Ped7g
Thu Jan 31, 2019 6:30 pm
Forum: Software
Topic: How to detect that DMA transfer is finished
Replies: 14
Views: 2279

Re: How to detect that DMA transfer is finished

I don't think they are capable to operate in parallel .. at least the original Z80 DMA was inhibiting the CPU completely IIRC (it's already quite some months since I read through that data sheet, so I'm not sure).
by Ped7g
Thu Jan 31, 2019 1:57 pm
Forum: ZX Spectrum Next
Topic: Update 42 - New graphics mode
Replies: 21
Views: 3229

Re: Update 42 - New graphics mode

... It's much more than that :) Allows for super fast graphics as well if you organize them properly And the Tilemap clip window description doesn't explain what happens in 80x32 mode. I went ahead in wiki and *guessed* the X-coordinates are then quadrupled, let me know if I got it wrong. Meanwhile...
by Ped7g
Tue Jan 29, 2019 3:52 pm
Forum: ZX Spectrum Next
Topic: Update 42 - New graphics mode
Replies: 21
Views: 3229

Re: Update 42 - New graphics mode

... Technical questions/remarks: There is now new clip window register 0x1B for tilemode. But 0x1C clip control still lists only S/L/U clip windows. Are there new bits for tilemode clip control? (W) reset / (R) index? ---- Global transparency $14 has in description "...and tilemap uses nextreg 0x??...