Ampro Corporation Littleboard 550 manual PDCE2, Pdrst

Chapter 3 Hardware

Pin #

31

32

33

34

35

36, 38

37

39

40

41

42

43

44

45

46

47

48

49

50

Signal	Description
PDD15	Disk Data 15 – Refer to PDD3 on pin-2 for more information.
PDCE2*	Primary Slave/Master Chip Select – This signal, along with CE1*, selects the
	CompactFlash card and indicates to the card when a byte or word operation is
	being performed. This signal always accesses the odd byte of the word.
NC	Not Connected (VS1*)
PDIOR*	Primary I/O Read Strobe – This signal is generated by the host and gates the
	I/O data onto the bus from the CompactFlash card when the card is
	configured to use the I/O interface.
PDIOW*	Primary I/O Write Strobe – This signal is generated by the host and clocks the
	I/O data on the Card Data bus into the CompactFlash card controller registers
	when the card is configured to use the I/O interface. The clock occurs on the
	negative to positive edge of the signal (trailing edge).
VCC	CF power – This voltage is determined by setting of JP3, CF Voltage Select
	(pins 1-2 = +5 volts ±5% Default, or pins 2-3 = +3.3 volts ±5%)
IRQ14	Interrupt Request 14 – IRQ 14 is asserted by drive (CF) when it has a pending
	interrupt (PIO transfer of data to or from the drive to the host).
Master*	Master/Slave – This pin determines the Master or Slave configuration of the
	CompactFlash by the jumper (JP4) setting. When this pin is grounded
	(jumper inserted), this device is configured as Master. When this pin is open
	(jumper removed), this device is configured as Slave.
NC	Not Connected (VS2*)
PDRST*	Primary IDE Reset – This input signal is the active low hardware reset from
	the host. If this pin goes high, it is used as the reset signal. This pin is driven
	high at power-up, causing a reset, and if left high will cause another reset.
PDIORDY	Primary I/O-DMA Channel Ready – When negated, extends the host transfer
	cycle of any host register access when the drive is not ready to respond to a
	data transfer request. High impedance if asserted.
NC	Not Connected (INPACK)
VCC	CF power – This voltage is determined by setting of JP3, CF Voltage Select
	(pins 1-2 = +5 volts ±5% Default, or pins 2-3 = +3.3 volts ±5% )
NU	Not used (Pull-up to VCC through 10k ohm resistor)
PD33/66	UDMA 33/66 Sense – Senses which DMA mode to use for the CF card.
D8	Disk Data – These signals (0 to 15) provide the disk data signals
D9	Disk Data – These signals (0 to 15) provide the disk data signals
D10	Disk Data – These signals (0 to 15) provide the disk data signals
GND	Ground

Notes: The shaded area denotes power or ground. The signals marked with * = Negative true logic.

CAUTION To prevent system hangs when using older CompactFlash cards, ensure your CompactFlash is compatible with UDMA 100 IDE hard disk drives. Consult your CompactFlash card vendor for UDMA 100 compatibility.

40 Reference Manual LittleBoard 550