Search found 2820 matches

by JonAbbott
Sat Feb 08, 2014 1:13 pm
Forum: Pi
Topic: Blitter support for VIDC1/20 and palette changes
Replies: 20
Views: 15476

Re: Blitter support for VIDC1/20 and palette changes

Great, if we can decide how we want the raster palette table(s) to look, I'll make a start on the changes to adffs.aborts.vidc1_abort / vidc20_abort as they're closely tied in with the IOC code I'm currently working on...calculating the timing etc. Option 1 A 16 word table per raster, with SSBBGGRR ...
by JonAbbott
Sat Feb 08, 2014 12:54 pm
Forum: Pi
Topic: IOC emulation
Replies: 12
Views: 9532

Re: IOC emulation

So on that basis - for IOC emulation, it's probably best to trigger the timer to start as soon as you've received the first T1 latch high and T1 latch low write. If you then receive a subsequent 'Go', reset the timer to the latch value. That explains the missing GO write then. I'll move the code th...
by JonAbbott
Sat Feb 08, 2014 12:45 pm
Forum: LCDGameModes
Topic: LCDGameModes VIDC20
Replies: 10
Views: 13855

Re: LCDGameModes VIDC20

in the back of my mind I thought that ADFFS cached the VIDC1 writes for translation, and fired them off together to VIDC20 at the same time? This would be slightly different behaviour. But we'll see if it works soon enough... What I normally do when hijacking RISC OS code, is to look at the origina...
by JonAbbott
Fri Feb 07, 2014 12:11 pm
Forum: Pi
Topic: IOC emulation
Replies: 12
Views: 9532

IOC emulation

I've coded IOC Timer 1 (device 6), Vsync (device 3) and the IRQv emulator. Could someone confirm my understanding of how IOC Timer 1 works: 1. T1 Latch Low / High are written with the timer value 2. Bit 6 of IRQA mask is set to enable the IRQ 3. T1 Go is written to start the timer 4. IRQ is raised I...
by JonAbbott
Fri Feb 07, 2014 10:51 am
Forum: Pi
Topic: Blitter support for VIDC1/20 and palette changes
Replies: 20
Views: 15476

Blitter support for VIDC1/20 and palette changes

Code that requires changing to support these are detailed below. Note that all VIDC1 register writes are translated to VIDC20 registers, so we only need to take account of VIDC20 values. The latest code is in /development/32bit/cpu on the dev site. adffs.vectors.DA2_frame_buffer blit_DA2_frame : set...
by JonAbbott
Fri Feb 07, 2014 9:04 am
Forum: LCDGameModes
Topic: LCDGameModes VIDC20
Replies: 10
Views: 13855

Re: LCDGameModes VIDC20

But the CallBack might be a problem. If LCDgm responds to the Service_ModeChanged by immediately patching the VIDC20 registers, this will happen before ADFFS has sent through the VIDC1 translations (which happens after the mode change has completed and control has returned to ADFFS), so ADFFS will ...
by JonAbbott
Thu Feb 06, 2014 5:20 pm
Forum: LCDGameModes
Topic: Re: LCDGameModes initialising
Replies: 2
Views: 5946

Re: LCDGameModes initialising

steve3000 wrote:I suspect you've done this to ensure LCDgm switches on when running on VIDC20 machines? However it shouldn't issue this command on pre-RiscPC computers, as there is no need since LCDGameModes switches on automatically on MonitorType 3 and 4.
That is why I added it, I'll correct it in the next beta.
by JonAbbott
Thu Feb 06, 2014 5:17 pm
Forum: LCDGameModes
Topic: LCDGameModes VIDC20
Replies: 10
Views: 13855

Re: LCDGameModes VIDC20

Ok, this can be done, but there is a real probability that the behaviour will be different to as it is now, since we'll have LCDgm updating VIDC20 registers in response to Service_ModeChanged, which may be at different times to ADFFS doing its VIDC1->VIDC20 translation. So I really need to understa...
by JonAbbott
Thu Feb 06, 2014 1:42 pm
Forum: LCDGameModes
Topic: LCDGameModes VIDC20
Replies: 10
Views: 13855

Re: LCDGameModes VIDC20

We simply need the module to check if VIDC20 is present when it's loaded and write VIDC20 registers instead of VIDC1 registers, so it's not dependent on ADFFS. ADFFS already handles type 0/1 mode extensions, feel free to lift the code if you want to add it to LCDgm, it's in adffs.service . It does h...
by JonAbbott
Thu Feb 06, 2014 1:08 pm
Forum: ADFFS
Topic: ADFFS 2.34 beta
Replies: 25
Views: 18059

Re: ADFFS 2.34 beta

It's firmware, as the problem is apparent in Linux as well. In Linux however you can use the FIQ split branch and force Linux down to USB 1 mode to resolve.