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Chapter 23
LCD Bus Interface (LCD-I/F)
Preliminary User’s Manual U17566EE1V2UM00
23.3 Timing
This section starts with the general timing and then presents examples of
consecutive write and read operations.
23.3.1
Timing dependencies
The following figure shows the general timing when the mod80 mode is used.
It illustrates the effect of the LBCYC0 and LBWST0 register settings. It explains
also the impact of LBCTL0.TCIS on the interrupt generation.
Figure 23-2
LCD Bus Interface timing (mod80 mode)
In mod80 mode, DBWR provides the write strobe WR and DBRD the read
strobe RD.
Note
1.
T is the clock period of the selected SPCLK.
2.
CYC is the chosen number of clock cycles (LBCYC0.CYC0). Always keep
LBCYC0.CYC0 > 2.
3.
WST is the chosen number of wait states (LBWST0). Always keep
LBWST0.SWST0 < (LBCYC0.CYC0 – 2).
The only difference in mod68 mode is, that DBWR provides the read/write R/W
strobe and DBRD the E strobe. The active edge of the E strobe is defined by
LBCTL0.EL0.
DBWR
DBRD
DBD[7:0]
Internal
interrupt
(TCIS=0)
on write
on read
(TCIS=1)
(WRITE)
Data
(WST+1) * T
CYC * T
Data
DBD[7:0]
(READ)
Read or write byte from/to LBDATA register by CPU or DMA
next byte
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