rtd cpuModule CME37786HX, User Manual

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CME37786HX RTD Embedded Technologies, Inc.
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PC/104 Bus Termination
Termination of PC/104 bus signals is not recommended since this cpuModule incorporates source
termination on bus signals and may cause malfunctions of the cpuModule.
RESETDRV O This line, active high, is used to reset the devices on the bus, at power-
on or after a reset command.
SA0-19 O Address bits 0 to 19: these lines are used to address the memory space
and the I/O space. SA0 is the least significant bit while SA19 is the most
significant bit.
SBHE* O This active-low signal indicates a transfer of the most significant data
byte (SD15-SD8).
SD8-15 I/O Data bits: these are the high-byte data bus lines. SD8 is the least signif-
icant bit; SD15 the most significant bit.
SD0-7 I/O Data bits: these are the low-byte data bus lines. SD0 is the least signifi-
cant bit; SD7 the most significant bit.
SMEMR* O Memory Read command, active low.
SMEMW* O Memory Write command, active low.
SYSCLK O System Clock, 8.0MHz with a 50% duty cycle. Only driven during ex-
ternal bus cycles.
TC O Terminal Count: this line is active high and indicates the conclusion of
a DMA transfer.
Table 25: PC/104 Bus Signals