HP AMD Geode E2047551001R, AMD Geode ECM-5510, AMD Geode GX466 manual 45

User’s Manual

2.4.19.1Signal Description – PC/104 Connector (CN7 + CN8) 2.4.19.1.1Address

Signal	Signal Description
	The address signals LA [23:17] define the selection of a 128KB section of memory
	space within the 16MB address range of the 16-bit data bus. These signals are
	active high. The validity of the MEMCS16# depends on these signals only. These
LA [17:23]	address lines are presented to the system with tri-state drivers. The permanent
	master drives these lines except when an alternate master cycle occurs; in this
	case, the temporary master drives these lines. The LA signals are not defined for
	I/O accesses.
SA [0:19]	System address. Address lines for the first one Megabyte of memory. SA [9:0]
	used for I/O addresses. SA0 is the least significant bit
	This signal is an active low signal, that indicates that a byte is being transferred on
SBHE#	the upper byte (SD [15:8]) of the 16 bit bus. All bus masters will drive this line with
	a tri-state driver.

2.4.19.1.2Data

Signal				Signal Description
	These signals are defined for the low order byte of the 16-bit data bus being the
	only bus for 8 bit PC-AT/PC104 adapter boards. Memory or I/O transfers on this
	part of the data bus are defined for 8-bit operations with even or odd addresses
	and for 16-bit operations for odd addresses only. The signals SA0 and SBHE# are
	used to define the data present on this bus:
		SBHE#	SA0	SD8-SD15	SD0-SD7	Action
SD [0:7]		0	0	ODD	EVEN	Word transfer
		0	1	ODD	ODD	Byte transfer on
						SD8-SD15
		1	0	X	EVEN	Byte transfer on
						SD0-SD7
		1	1	X	ODD	Byte transfer on
						SD7-
SD [8:15]	These signals are defined for the high order byte of the 16-bit data bus. Memory or
	I/O transfers on this part of the bus are defined when SBHE# is active.

ECM-5510 User’s Manual 45