![Tadpole SPARCbook 3 series Скачать руководство пользователя страница 172](http://html2.mh-extra.com/html/tadpole/sparcbook-3-series/sparcbook-3-series_reference-manual_3192948172.webp)
11-22
Display Interface
RAMDAC
11.4.1 RAMDAC host interface
The RAMDAC host interface is mapped through the RAMDAC space of
the P9100 at 0x38000200. In response to addresses in the RAMDAC
region, the Power 9100 generates register select signals to select the target
register.
The RAMDAC provides a byte-wide control interface allowing control
registers and color lookup tables to be accessed. There are eight register
locations that can be accessed directly. All other registers are accessed by
first writing to internal index registers to specify the control register or
cursor register to be accessed.
Note
It is necessary to insert software delays between accesses to the RAMDAC registers
and palettes. A convenient way of doing this is to read the Power 9100 configuration
register between each RAMDAC access.
The RAMDAC internal locations can be accessed using the addresses
shown in Table 6-13.
11.4.2 Control register accesses
The control registers are used to program the RAMDAC to suit its
operating environment. Setable properties include pixel unpacking and
pixel depth, serial clock and multiplexor rates, and blinking.
The column ‘INDEX’ in Table 11-12 shows the value that should be
written into the Index High and Index Low Registers in order to read or
write internal locations. For example, to write to the Power Management
register at index 0x0005, first the value 0x05 would be written Index Low
CPU Address
Register
38000200
Palette Address Register (write mode)
38000208
Palette Data
38000210
Pixel Mask
38000218
Palette Address (read mode)
38000220
Register Index Low
38000228
Register Index High
38000230
Register Data
38000238
Index Control
Table 11-11 Directly Addressed RAMDAC Registers
S3GX_TRMBook Page 22 Friday, September 19, 1997 11:39 am
Содержание SPARCbook 3 series
Страница 1: ...Series Technical Reference Manual 980327 02 3 S3GX_TRMBook Page i Friday September 19 1997 11 39 am...
Страница 8: ...viii S3GX_TRMBook Page viii Friday September 19 1997 11 39 am...
Страница 28: ...1 16 Architecture Overview Microcontroller Subsystem S3GX_TRMBook Page 16 Friday September 19 1997 11 39 am...
Страница 44: ...2 16 The SPARC CPU SBus Controller S3GX_TRMBook Page 16 Friday September 19 1997 11 39 am...
Страница 76: ...5 8 SCSI Controller DMA Support S3GX_TRMBook Page 8 Friday September 19 1997 11 39 am...
Страница 82: ...6 6 Ethernet Interface DMA Support for Network Operations S3GX_TRMBook Page 6 Friday September 19 1997 11 39 am...
Страница 96: ...7 14 PCMCIA Interface Microcontroller Registers S3GX_TRMBook Page 14 Friday September 19 1997 11 39 am...
Страница 146: ...9 28 MODEM Class 2 Fax Command Set S3GX_TRMBook Page 28 Friday September 19 1997 11 39 am...
Страница 180: ...11 30 Display Interface RAMDAC S3GX_TRMBook Page 30 Friday September 19 1997 11 39 am...
Страница 210: ...B 10 Connector Information Removable Hard Drive SCSI Connector S3GX_TRMBook Page 10 Friday September 19 1997 11 39 am...
Страница 216: ...Index vi S3GX_TRMBook Page vi Friday September 19 1997 11 39 am...