MB87P2020 Datasheet, PDF (351/356 Pages) Fujitsu Component Limited. – Colour LCD/CRT/TV Controller

Hints and Restrictions
GDC_FIFO_INP((dword*)BuildIfData(x,y,layer),1,0);
}
// ----------------------------------------
// send NoOp command to force FIFO flush
// ----------------------------------------
GDC_CMD_NOP();
// ----------------------------------------
// wait for data in OF
// ----------------------------------------
G0OFUL_UL = pkg_size;
while (G0FLNOM_OFH==0);
// read data from output FIFO
for (jj=0;jj<pkg_size;jj++) {
data[amount++] = G0OFIFO;
}
Figure 2-2: Example for package size calculation and read back
2.13 Display Interface Re-configuration
If modification of the display interface record (DIR, part of GPU) is used to re-configure the physical size
and display timing (PHSIZE, MTIMODD, MTIMEVEN) it can happen that display output can’t be activat-
ed again. This is important for multisync systems which work with different video resolutions (hot config-
urable in running application). The error was discovered only if switching from higher to lower display
resolution.
Intended configuration method was:
1. MTIMON = 0
2. reconfigure DIR
3. MTIMON = 1
To avoid this error it is recommended to use general hardware master reset and reconfigure the whole GDC
device:
1. CLKPDR_MRST = 1
2. CLKPDR_MRST = 0
3. reconfigure whole GDC
4. MTIMON = 1
.
Table 2-16: GPU sync timing change
Subject
Description
Classification
Effects without
workaround
Solution/Workaround
Description
If GPU display resolution is changed GPU may hang with no output (black
display).
HW restriction
GPU may hang at resolution change from higher to lower resolutions.
Only a hardware reset (RESETX pin or CLKPDR_MRST) and re-configura-
tion reactivates GPU. This has to be considered if changing sync timing at
runtime is required.
Restrictions
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