The ZX Spectrum Next forum

The hardware spi interface on the pi0 turned out not to be as useful as expected so it's very likely that the pi will need a uart connection to allow reasonable communication with the pi running linux. Beyond that there is a lot of leeway on how things end up. I don't know if this will be settled be...

z88dk has been compiled for the pi0 and I believe Tim has been trying it on the next. But I would be very surprised if the optimizing compiler (zsdcc) can run at a reasonable speed on the pi0. The other compiler (sccz80) and the assembler / linker tools should be ok though.

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...

mike opened this post 2017 and said this would be happening for a second batch, originaly 1000(roughly) nexts would be produced, were all hoping that when the final batch of keys and cases have been made the team would be better off asking for a larger number made 2000+, this would decrease cost an...

Sinclair Basic does not contain any bitwise operators but Next basic does. See page 24 "Integer Variables and Expressions": https://gitlab.com/thesmog358/tbblue/blob/master/docs/nextzxos/NextBASIC_New_Commands_and_Features.pdf When reading/writing nextreg in basic using OUTs, you have to make sure t...

They can't operate in parallel. There is only one address bus and one data bus in the system and either the CPU is controlling them or the DMA is controlling them.

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. Clipping windows are always applied in normal resolution. The high horizontal resolution modes (80x32 tilemap ...

The kickstarter was finished more than a year ago. It raises a pool of money that is used to develop the product and build the machines for backers. There's no extra pool of money or parts to build more units for others wanting them later. For that, more money will be needed up front to buy parts an...

Does this also mean that in burst mode the cpu is slowed down by the dma? Yes but it's not by very much. If you're doing 32kHz sampled audio, you're sending about 640 bytes of sampled data in a 50Hz frame. Each sample takes 4 cycles plus maybe a couple cycles overhead for the DMA to hand back the b...

If you're using continuous mode (as you almost always will be), the dma is finished by the time your next instruction executes. This is because the DMA is given the bus by the CPU which waits until the DMA gives it back. In continuous mode, the DMA does the entire transfer before giving it back. In ...