WinSystems LBC- 486Plus, Руководство по эксплуатации

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High Re fresh Modes
Mode
#
(Hex)
Dis play
Mode
Col ors
Text
Dis play
Font
Size Pixel
Reso lu tion
Dot
Clock
(MHz)
Hori zon tal
Fre quency
(KHz)
Ver ti cal
Fre quency
(Hz)
Video
Memory
CRT
CODE
12 Planar 16 80 X 30 8 X 16 640 X 480 31.50 37.5 75 256KB B,C
30 8- Bit Linear 256 80 X 30 8 X 16 640 X 480 31.50 37.5 75 256KB C
79 Packed Pixel 256 80 X 30 8 X 16 640 X 480 31.50 37.5 75 512KB C
6A,70 Planar 16 100 X 37 8 X 16 800 X 600 49.50 46.9 75 512KB C
32 8- Bit Linear 256 100 X 37 8 X 16 800 X 600 49.50 46.9 75 1MB C
7C Packed Pixel 256 100 X 37 8 X 16 800 X 600 49.50 46.9 75 1MB C
2.22 Eth er net Con figu ra tion
The Eth er net sec tion of the LBC- Plus uses the Na tional 83905 AT/LAN TIC Lo cal Area Net work
Twisted- Pair In ter face con trol ler. The AT/LAN TIC con trol ler is a CMOS/VLSI de vice used in the im -
ple men ta tion of CSMA/CD lo cal area net works. Sup ported net work in ter faces in clude 10BASE5 or
10BASE2 via an ex ter nal trans ceiver con nected to the AUI port, and twisted pair Eth er net (10BASE-T)
us ing the on board trans ceiver. The AT/LAN TIC pro vides the Eth er net Me dia Ac cess Con trol (MAC),
Encode- Decode (EN DEC) with an AUI in ter face, and 10BASE-T trans ceiver func tions in ac cor dance
with IEEE 802.3 stan dards.
This func tional block in cor po rates the re ceiver, trans mit ter, col li sion heart beat. loop back jab ber,
and link in teg rity blocks as de fined in the stan dard. The trans ceiver when com bined with the equali za -
tion re sis tors, trans mit/re ceive fil ters, and pulse trans form ers pro vide a com plete physi cal in ter face
from the AT/LAN TIC Con trol ler EN DEC mod ule and the twisted- pair me dium.
The in te grated EN DEC mod ule al lows the Man ches ter en cod ing and de cod ing via a dif fer en tial
trans ceiver and phase- lock- loop de coder at 10 Mbit/sec. Also in cluded are a col li sion de tect trans la tor
and di ag nos tic loop back ca pa bil ity. The EN DEC mod ule in ter faces di rectly to the trans ceiver mod ule
and pro vides full IEEE com pli ant AUI (At tach ment Unit In ter face) for con nec tion to other me dia trans -
ceiv ers.
The Me dia Ac cess Con trol (MAC) func tion is pro vided by the Net work In ter face Con trol (NIC)
mod ule which pro vides sim ple and ef fi cient packet trans mis sion and re cep tion con trol by means of off-
chip mem ory which can be ac cessed ei ther through an I/O port or mapped into the sys tem mem ory map.
An on board EPROM holds the Eth er net Ad dress and op tional con figu ra tion in for ma tion. This al -
lows for “jumper less” con figu ra tion us ing soft ware to con fig ure the board for its op er at ing mode, me -
dia type, I/O ad dress, in ter rupt, etc.
991206 OPERATIONS MANUAL LBC-Plus Page 2 - 29
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