OM11077 NXP Semiconductors, OM11077 Datasheet - Page 305

• Manufacturer Part Number: OM11077
• Description: MODULE DIMM LPC2478 ARM7
• Manufacturer: NXP Semiconductors

Specifications of OM11077

• Accessory Type: Module Card
• For Use With/related Products: ARM-57TS-LPC2478
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 568-4742

NXP Semiconductors
UM10237_4
User manual
7.2.1 Horizontal timing restrictions
Table 261. Horizontal Timing register (LCD_TIMH, RW - 0xFFE1 0000)
DMA requests new data at the start of a horizontal display line. Some time must be
allowed for the DMA transfer and for data to propagate down the FIFO path in the LCD
interface. The data path latency forces some restrictions on the usable minimum values
for horizontal porch width in STN mode. The minimum values are HSW = 2 and HBP = 2.
Single panel mode:
Dual panel mode:
Bits
31:24
23:16
15:8
7:2
1:0
•
•
•
•
•
•
•
HSW = 3 pixel clock cycles
HBP = 5 pixel clock cycles
HFP = 5 pixel clock cycles
Panel Clock Divisor (PCD) = 1 (LCDCLK / 3)
HSW = 3 pixel clock cycles
HBP = 5 pixel clock cycles
HFP = 5 pixel clock cycles
Function
HBP
HFP
HSW
PPL
reserved
Rev. 04 — 26 August 2009
Description
Horizontal back porch.
The 8-bit HBP field is used to specify the number of pixel clock
periods inserted at the beginning of each line or row of pixels.
After the line clock for the previous line has been deasserted, the
value in HBP counts the number of pixel clocks to wait before
starting the next display line. HBP can generate a delay of 1-256
pixel clock cycles. Program with desired value minus 1.
Horizontal front porch.
The 8-bit HFP field sets the number of pixel clock intervals at the
end of each line or row of pixels, before the LCD line clock is
pulsed. When a complete line of pixels is transmitted to the LCD
driver, the value in HFP counts the number of pixel clocks to wait
before asserting the line clock. HFP can generate a period of
1-256 pixel clock cycles. Program with desired value minus 1.
Horizontal synchronization pulse width.
The 8-bit HSW field specifies the pulse width of the line clock in
passive mode, or the horizontal synchronization pulse in active
mode. Program with desired value minus 1.
Pixels-per-line.
The PPL bit field specifies the number of pixels in each line or
row of the screen. PPL is a 6-bit value that represents between
16 and 1024 pixels per line. PPL counts the number of pixel
clocks that occur before the HFP is applied.
Program the value required divided by 16, minus 1. Actual
pixels-per-line = 16 * (PPL + 1). For example, to obtain 320
pixels per line, program PPL as (320/16) -1 = 19.
Reserved, user software should not write ones to reserved bits.
The value read from a reserved bit is not defined.
Chapter 12: LPC24XX LCD controller
UM10237
© NXP B.V. 2009. All rights reserved.
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Reset
value
0x0
0x0
0x0
0x0
-