GXM datasheet(152/244 Pages) NSC

152 / 244 page

www.national.com

152

Revision 3.1

Integrated Functions (Continued)

31:0

DISPLAY FIFO

DIAGNOSTIC

DATA

Display FIFO Diagnostic Read or Write Data: Before this register is accessed, the DIAG bit in

DC_GENERAL_CFG register should be set high and the DFLE bit should be set low. Since, each

FIFO entry is 64 bits, an even number of write operations should be performed. Each pair of write

operations will cause the FIFO write pointer to increment automatically. After all write operations

have been performed, a single read of don't care data should be performed to load data into the out-

put latch. Each subsequent read will contain the appropriate data which was previously written.

Each pair of read operations will cause the FIFO read pointer to increment automatically. A pause of

at least four core clocks should be allowed between subsequent read operations to allow adequate

time for the shift to take place.

GX_BASE+837Ch-837Fh

DC_CFIFO_DIAG Register (R/W)

Default Value = xxxxxxxxh

31:0

COMPRESSED

FIFO DIAGNOS-

TIC DATA

Compressed Data FIFO Diagnostic Read or Write Data: Before this register is accessed, the

DIAG bit in DC_GENERAL_CFG register should be set high and the DFLE bit should be set low.

Also, the DIAG bit in DC_OUTPUT_CFG should be set high and the CFRW bit in

DC_OUTPUT_CFG should be set low. After each write, the FIFO write pointer will automatically

increment. After all write operations have been performed, the CFRW bit of DC_OUTPUT_CFG

should be set high to enable read addresses to the FIFO and a single read of don't care data should

be performed to load data into the output latch. Each subsequent read will contain the appropriate

data which was previously written. After each read, the FIFO read pointer will automatically incre-

ment.

Table 4-35. Display Controller Palette and RAM Diagnostic Registers (Continued)

Bit

Name

Description

GXM Datasheet(PDF) 152 Page - National Semiconductor (TI)