MB87P2020 Datasheet, PDF (82/356 Pages) Fujitsu Component Limited. – Colour LCD/CRT/TV Controller

MB87J2120, MB87P2020-A Hardware Manual
3 and 1-4 as it is used for IPA and DPA access methods.For LDR entries of PHA only row bits are valid,
not used
row
bank
column
byte
31
23 22
12 11 10 9
21 0
Figure 1-3: Physical address format (Lavender)
not used
row
31
20 19
Figure 1-4: Physical address format (Jasmine)
column
byte
10 9
21 0
lower bits are fixed to ’0’. This is due to the physical start address is aligned on the row grid.
For comparison, logical address format is shown in figure 1-5.
Layer [3:2]
X
Layer[1:0]
Y
31 30 29
16 15 14 13
0
Figure 1-5: Logical address format
Now back to the relationship between logical pixel address containing layer, X and Y location and the phys-
ical mapping of the pixel data. The needed bits per pixel line of the layer can be calculated as¹
XBits = DomSzX << Shift = DomSzX * bpp
Remark:
Expression ’<< Shift’ interpretable as ’* bpp’ with the restriction
that
bpp
has
a
value
range
of
power
of
two
{
2⁰,
2¹,
2²,
2³,
2⁴,
5
2
}
For determining Shift value from its Color Space Code see table 1-5. It depends on the layer number and
how CSPACE is configured for it.
Layer memory can only be divided into whole numbered parts of rows in each dimension. Each row seg-
ment has a width of 8 words. Lavender uses 2 adjacent banks with same row number, thus a virtual row of
16 words is formed. From the number of bits the needed number of horizontal memory rows is
XRows = XBits[18:9] + (XBits[8:0]? 1: 0) (for Lavender)
XRows = XBits[18:8] + (XBits[7:0]? 1: 0) (for Jasmine)
Finally the row, bank and column addresses can be derived from the logical address components and this
temporary values. Con catenation of row, bank and column address enhanced with 2 bits for byte addressing
results in the physical address.
RA = Y[13:6] * XRows + (X << Shift)[18:9] (for Lavender)
RA = Y[13:5] * XRows + (X << Shift)[18:8] (for Jasmine)
BA = {Y[5], (X << Shift)[8]}
(for Lavender only)
CA = {Y[4:0], (X << Shift)[7:5]}
1.Squared brackets stand for vector slices, curly braces are vector combinations.
Page 82