CSA Mega-Midget Racer, User Manual

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4) Populate “ BANK 1 ” of the daughter-board fully prior to populating
“ BANK 2 ”. Carefully place each DRAM chip in its socket. Observe
correct “notch” orientation and press firmly until all pins of each
DRAM chip are fully seated in its respective socket.
Jumper Settings
The CSA Mega-Memory DRAM daughter-board has several user selectable
jumpers that specify the configuration of the daughter-board. The user
m u s t s e t t h e s e j u m p e r s t o t h e i r a p p r o p r i a t e s e t t i n g s i n o r d e r f o r t h e
s y s t e m t o f u n c t i o n p r o p e r l y. T h e f o l l o w i n g p a r a g r a p h s d e s c r i b e t h e
jumpers in detail.
Jumper JP1 , located near the large, square controller chip on the daughter-board,
needs to be set according to the size of the DRAM chips being used. If 256kx4 DRAM
chips are used, then
JP1 should be set to short (connect) pins 2 and 3 (labeled
“ 256kX4 DRAM ”). If 1Mx4 DRAM chips are used, then JP1 should be set to short
pins 1 and 2 (labeled “ 1MX4 DRAM ’).
Jumper JP2 , located next to JP1 , must be set to short (connect) pins 2 and 3. Your
board may already be hardwired at the factory.
Jumper W1 , labeled “ SIZE ”, is also set according to the size of the DRAM chips being
used. If 1Mx4 DRAM chips are being used, a black shorting block should be placed over
jumper
W1 . For 256kx4 DRAM chips, W1 should be open.
Jumper W2 , labeled “ BANKS ”, is set according to how many banks of DRAM are
installed. If both banks are fully populated with appropriate DRAM chips, a shorting
block should be placed on
W2 . If only Bank 1 is populated, W2 should be open.
Jumpers W3 , labeled “ PAGE ”, and W4 , labeled “ STATIC ”, are set according to the type
of DRAM being used. If all DRAM chips installed are Page Mode DRAMs, a shorting block
should be placed on
W3 . If all DRAM chips installed are Static Column Mode DRAMs, a
shorting block should be placed on W4 . For all other cases, or if you are not sure what
type of DRAM is installed, W3 and W4 should be open.
Jumpers W5 and W6 , labeled “ ACCESS TIME ”, are set according to the speed, or
access time, of the DRAM being used. Use the table below to determine the settings for
jumpers
W5 and W6 . Use the access time of the slowest DRAM chip installed to ensure
proper operation (the slowest chip has the largest access time). DRAM chips with
access times greater than 100ns cannot be used with the CSA
Mega-Memory DRAM
daughter-board.
Access Time Jumper W5 Jumper W6
100ns open open
80ns open shorted
70ns shorted open
60ns shorted shorted
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