Widescreen Screen Resolution with RISC OS 5.24 on RPCemu

I’ve just installed RISC OS 5.24 on RPCemu, running on a Windows 10 laptop with a 1600×900px screen. I want to run RISC OS full screen at the native resolution, but the list of monitors in the Screens bit of Configure doesn’t have any offering that resolution.

I tried adding a Monitor Definition File (MDF) to !Boot.Resources.Configure.Monitors.Other but as I was essentially inferring the correct content by looking at other MDFs I must have got it wrong, attempting to use it gives the error “Inconsistent Parameters”.

Any ideas?

Thanks,
Andrew

Have you tried AnyMode module?
That’s what I use on my RPCEmu setup, using 5.24.

I’ve also got this MDF (I tend to use the 1440×850):

	
Modefile written by !MakeModes version 0.26 (14th December 1994)

file_format:1

monitor_title:Apple MacBook Air

DPMS_state:3

	
1024×768@60Hz reduced blanking VESA CVT 0.79M3-R

startmode

mode_name:1024 × 768

x_res:1024

y_res:768

pixel_rate:56000

h_timings:32,80,0,1024,0,48

v_timings:4,15,0,768,0,3

sync_pol:3

endmode


	
1024 × 768 (96Hz)

startmode

mode_name:1024 × 768

x_res:1024

y_res:768

pixel_rate:128000

h_timings:128,156,58,1024,140,194

v_timings:3,16,0,768,0,1

sync_pol:3

endmode


	
1280×720@60Hz reduced blanking VESA CVT 0.79M3-R

startmode

mode_name:1280 × 720

x_res:1280

y_res:720

pixel_rate:64000

h_timings:32,80,0,1280,0,48

v_timings:5,13,0,720,0,3

sync_pol:3

endmode


	
1280 × 768 (83Hz)

startmode

mode_name:1280 × 768

x_res:1280

y_res:768

pixel_rate:128000

h_timings:128,156,58,1280,140,194

v_timings:3,16,0,768,0,1

sync_pol:3

endmode


	
1280×720@50Hz CEA-861B Format 19

startmode

mode_name:1280 × 720

x_res:1280

y_res:720

pixel_rate:74250

h_timings:40,220,0,1280,0,440

v_timings:5,5,0,720,0,20

sync_pol:3

endmode


	
1280×720@60Hz CEA-861B Format 4

startmode

mode_name:1280 × 720

x_res:1280

y_res:720

pixel_rate:74250

h_timings:40,220,0,1280,0,110

v_timings:5,5,0,720,0,20

sync_pol:3

endmode


	
1440 × 850 (60Hz)

startmode

mode_name:1440 × 850

x_res:1440

y_res:850

pixel_rate:75955

h_timings:10,10,16,1440,0,0

v_timings:10,0,0,850,0,0

sync_pol:0

endmode


	
1440 × 850 (70Hz)

startmode

mode_name:1440 × 850

x_res:1440

y_res:850

pixel_rate:140000

h_timings:128,156,58,1440,140,0

v_timings:3,16,0,850,0,1

sync_pol:0

endmode


	
End

(They should be hashes at the start of each entry – the formatting here decides to make it a list)

(They should be hashes at the start of each entry – the formatting here decides to make it a list)

I tend to use HTML <pre> tags for anything like this

# Look ma,
# no numbers!

Which you can get like this (I believe people have said the newlines around the <pre> tags are important):

This creatively tweaked 1680×1050 works here on RPCEmu 0.9.0 on OS5.24 on Ubuntu 18.04 on VMWare Fusion on an iMac running High Sierra.

# 1600 x 900 (30Hz)
startmode
mode_name:1600 x 900
x_res:1600
y_res:900
pixel_rate:55000
h_timings:10,10,56,1600,40,0
v_timings:10,0,75,900,75,0
sync_pol:0
endmode

A cvt generated MDF failed to work on OS5.24, it simply did not appear in the list, but was OK on OS4.02.

*cvt 1600 900 60

# 1600 x 900 (60.00Hz) 32bit (CVT)
startmode
mode_name: 1600 x 900
x_res:1600
y_res:900
pixel_rate:118250
h_timings:168,256,0,1600,0,88
v_timings:5,26,0,900,0,3
sync_pol:3
endmode

A 30Hz cvt MDF did work on OS5.24.

*cvt 1600 900 30

# 1600 x 900 (30.00Hz) 32bit (CVT)
startmode
mode_name: 1600 x 900
x_res:1600
y_res:900
pixel_rate:55000
h_timings:160,200,0,1600,0,40
v_timings:5,11,0,900,0,3
sync_pol:3
endmode

A cvt generated MDF failed to work on OS5.24, it simply did not appear in the list, but was OK on OS4.02.

The VIDC driver in RISC OS 5 enforces a max pixel rate limit of 110MHz (the suggested safe limit specified in the RiscPC TRM); perhaps earlier driver versions used higher limits, or omitted the check completely.

I’m not sure how things are with the new Qt-based version of RPCEmu, but I think the Allegro versions ignored the programmed VIDC clock rates and always refreshed the screen at 60Hz. So for your use case the difference between the 60Hz and 30Hz versions may be insignificant.

The VIDC driver in RISC OS 5 enforces a max pixel rate limit of 110MHz

Thanks for that info.

I’m not sure how things are with the new Qt-based version of RPCEmu

I am on the new Qt version, and did fail initially to give the RPCEmu version in my earlier post!

Is there anyway of changing RO5 – in the past – there was a command let you choose the max pixel rate – instead of using very low screen refreshes like 10hz.

Thanks everyone for your replies. I used AnyMode, and after figuring out that I needed to set the correct filetype after downloading it on windows and saving it in HostFS, it worked perfectly.

For reference, setting filetype, in this case for a Module:

Within Windows add “,FFA” to the filename (note the comma)
OR
Within RISC OS, middle/menu mouse click on the file, second menu option “File ‘AnyMode’→”, “Set Type →”, you can either enter the Hex code for a Module “FFA”, or type “Module”

A list of RISC OS filetypes and corresponding HEX codes may be found here:

https://en.wikipedia.org/wiki/List_of_RISC_OS_filetypes