Document available video modes for ZX frame buffers, which one will be

picked up at boot time depending on which monitor you plug in, and the
lack of any software way to change the resolution (yet).

1 files changed, 44 insertions, 1 deletions

diff --git a/share/man/man4/man4.sparc/zx.4 b/share/man/man4/man4.sparc/zx.4
index 41a122e6207..1b10be4c7c2 100644
--- a/share/man/man4/man4.sparc/zx.4
+++ b/share/man/man4/man4.sparc/zx.4
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: zx.4,v 1.3 2003/03/10 20:50:37 miod Exp $
+.\"	$OpenBSD: zx.4,v 1.4 2003/03/10 23:22:34 miod Exp $
 .\" Copyright (c) 2003 Miodrag Vallat.  All rights reserved.
 .\"
 .\" Redistribution and use in source and binary forms, with or without
@@ -49,6 +49,46 @@ It does not provide direct device driver entry points
 but makes its functions available via the internal
 .Xr wsdisplay 4
 interface.
+.Sh DISPLAY RESOLUTION
+The following resolutions are supported by the ZX frame buffer:
+.Bl -column "Resolution" "Refresh Rate"
+.It Li Resolution Ta "Refresh Rate"
+.It " "
+.It Li 1280x1024 Ta 76 Hz Ta Non-interlaced
+.It Li 1280x1024 Ta 67 Hz Ta Non-interlaced
+.It Li 1152x900 Ta 76 Hz Ta Non-interlaced
+.It Li 1152x900 Ta 66 Hz Ta Non-interlaced
+.It Li 1024x768 Ta 76 Hz Ta Non-interlaced
+.It Li 1024x768 Ta 60 Hz Ta Non-interlaced
+.\" Is it worth documenting the Stereo and TV modes?
+.It Li 960x680 Ta 112 Hz Ta "Stereo, non-interlaced"
+.It Li "" Ta "" Ta "56 Hz field rate per eye"
+.It Li 960x680 Ta 108 Hz Ta "Stereo, non-interlaced"
+.It Li "" Ta "" Ta "54 Hz field rate per eye"
+.It Li 770x575 Ta 50 Hz Ta "Interlaced - PAL"
+.It Li 640x480 Ta 59.94 Hz Ta "Interlaced - NTSC"
+.El
+.Pp
+If the ZX frame buffer is connected to a monitor at boot time, it will
+select its display resolution depending of the monitor
+.Sq select code
+provided by the 13W3 connector.
+If the frame buffer is not connected to a monitor, the default resolution
+of 1152x900 at 66 Hz will be selected.
+The selected resolutions are:
+.Bl -column "sense code" "Resolution" "Refresh" "Monitor"
+.It Li Monitor Ta Resolution Ta Refresh Ta Monitor
+.It Li "sense code" Ta "" Ta Rate Ta Type
+.It " "
+.It Li 0 Ta 1024x768  Ta "76 Hz" Ta X449A
+.It Li 1 Ta 1152x900  Ta "66 Hz"
+.It Li 2 Ta 1280x1024 Ta "76 Hz" Ta X248A, GDM-205S
+.It Li 3 Ta 1152x900  Ta "66 Hz" Ta GDM-1955A15, GDM-1604A15, CPD-1790
+.It Li 4 Ta 1280x1024 Ta "67 Hz" Ta GDM-20D10, GDM-1962
+.It Li 5 Ta 1152x900  Ta "66 Hz"
+.It Li 6 Ta 1152x900  Ta "76 Hz" Ta GDM-1662B, 17SMM4
+.It Li 7 Ta 1152x900  Ta "66 Hz"
+.El
 .Sh SEE ALSO
 .Xr agten 4 ,
 .Xr bwtwo 4 ,
@@ -72,3 +112,6 @@ interface.
 .Sh CAVEATS
 The ZX and TurboZX cards will not function in a sun4c class machine or
 in an SBus expansion box, due to PROM limitations.
+.Pp
+There is currently no software interface to change the frame buffer
+resolution at runtime.