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   1 NE_LEM1802 v1.0
   2
   3                                      \ |  ___
   4                                    |\ \|  ___
   5                                    | \
   6
   7                                  NYA ELEKTRISKA
   8                              innovation information
   9
  10
  11
  12
  13 DCPU-16 Hardware Info:
  14     Name: LEM1802 - Low Energy Monitor
  15     ID: 0x7349f615, version: 0x1802
  16     Manufacturer: 0x1c6c8b36 (NYA_ELEKTRISKA)
  17
  18
  19 Description:
  20     The LEM1802 is a 128x96 pixel color display compatible with the DCPU-16.
  21     The display is made up of 32x12 16 bit cells. Each cell displays one
  22     monochrome 4x8 pixel character out of 128 available. Each cell has its own
  23     foreground and background color out of a palette of 16 colors.
  24
  25     The LEM1802 is fully backwards compatible with LEM1801 (0x7349f615/0x1801),
  26     and adds support for custom palettes and fixes the double buffer color
  27     bleed bug.
  28
  29
  30 Interrupt behavior:
  31     When a HWI is received by the LEM1802, it reads the A register and does one
  32     of the following actions:
  33
  34     0: MEM_MAP_SCREEN
  35        Reads the B register, and maps the video ram to DCPU-16 ram starting
  36        at address B. See below for a description of video ram.
  37        If B is 0, the screen is disconnected.
  38        When the screen goes from 0 to any other value, the the LEM1802 takes
  39        about one second to start up. Other interrupts sent during this time
  40        are still processed.
  41     1: MEM_MAP_FONT
  42        Reads the B register, and maps the font ram to DCPU-16 ram starting
  43        at address B. See below for a description of font ram.
  44        If B is 0, the default font is used instead.
  45     2: MEM_MAP_PALETTE
  46        Reads the B register, and maps the palette ram to DCPU-16 ram starting
  47        at address B. See below for a description of palette ram.
  48        If B is 0, the default palette is used instead.
  49     3: SET_BORDER_COLOR
  50        Reads the B register, and sets the border color to palette index B&0xF
  51     4: MEM_DUMP_FONT
  52        Reads the B register, and writes the default font data to DCPU-16 ram
  53        starting at address B.
  54        Halts the DCPU-16 for 256 cycles
  55     5: MEM_DUMP_PALETTE
  56        Reads the B register, and writes the default palette data to DCPU-16
  57        ram starting at address B.
  58        Halts the DCPU-16 for 16 cycles
  59
  60
  61 Video ram:
  62     The LEM1802 has no internal video ram, but rather relies on being assigned
  63     an area of the DCPU-16 ram. The size of this area is 386 words, and is
  64     made up of 32x12 cells of the following bit format (in LSB-0):
  65         ffffbbbbBccccccc
  66     The lowest 7 bits (ccccccc) select define character to display.
  67     ffff and bbbb select which foreground and background color to use.
  68     If B (bit 7) is set the character color will blink slowly.
  69
  70
  71 Font ram:
  72     The LEM1802 has a default built in font. If the user chooses, they may
  73     supply their own font by mapping a 256 word memory region with two words
  74     per character in the 128 character font.
  75     By setting bits in these words, different characters and graphics can be
  76     achieved. For example, the character F looks like this:
  77        word0 = 1111111100001001
  78        word1 = 0000100100000000
  79     Or, split into octets:
  80        word0 = 11111111 /
  81                00001001
  82        word1 = 00001001 /
  83                00000000
  84
  85
  86 Palette ram:
  87    The LEM1802 has a default built in palette. If the user chooses, they may
  88    supply their own palette by mapping a 16 word memory region with one word
  89    per palette entry in the 16 color palette.
  90    Each color entry has the following bit format (in LSB-0):
  91        0000rrrrggggbbbb
  92    Where r, g, b are the red, green and blue channels. A higher value means a
  93    lighter color.
  94
  95
  96 A message from Ola:
  97    Hello!
  98
  99    It is fun to see that so many people use our products. When I was a small
 100    boy, my dad used to tell me "Ola, take care of those who understand less
 101    than you. Lack of knowledge is dangerous, but too much is worse".
 102    Here at Nya Elektriska have we always tried to improve mankind by showing
 103    them the tools required to improve and reach their true potential.
 104    Together, you will wake up in time.
 105
 106    - Ola Kristian Carlsson