Ampro Corporation Littleboard 550 用户手册
Chapter 3
Hardware
LittleBoard 550
Reference Manual
37
Pin #
Signal
Description
All Task File operations occur in byte mode on the low order bus D0-D7, while
all data transfers are 16 bit using D0-D15 to provide the disk data signals.
all data transfers are 16 bit using D0-D15 to provide the disk data signals.
4
SDD8
Secondary Disk Data 8 – Refer to SDD7 on pin-2 for more information.
5
SDD6
Secondary Disk Data 6 – Refer to SDD7 on pin-2 for more information.
6
SDD9
Secondary Disk Data 9 – Refer to SDD7 on pin-2 for more information.
7
SDD5
Secondary Disk Data 5 – Refer to SDD7 on pin-2 for more information.
8
SDD10
Secondary Disk Data 10 – Refer to SDD7 on pin-2 for more information.
9
SDD4
Secondary Disk Data 4 – Refer to SDD7 on pin-2 for more information.
10
SDD11
Secondary Disk Data 11 – Refer to SDD7 on pin-2 for more information.
11
SDD3
Secondary Disk Data 3 – Refer to SDD7 on pin-2 for more information.
12
SDD12
Secondary Disk Data 12 – Refer to SDD7 on pin-2 for more information.
13
SDD2
Secondary Disk Data 2 – Refer to SDD7 on pin-2 for more information.
14
SDD13
Secondary Disk Data 13 – Refer to SDD7 on pin-2 for more information.
15
SDD1
Secondary Disk Data 1 – Refer to SDD7 on pin-2 for more information.
16
SDD14
Secondary Disk Data 14 – Refer to SDD7 on pin-2 for more information.
17
SDD0
Secondary Disk Data 0 – Refer to SDD7 on pin-2 for more information.
18
SDD15
Secondary Disk Data 15 – Refer to SDD7 on pin-2 for more information.
19
GND
Ground
20
NC/Key
Not connected / Key pin plug
21
SDREQ
Secondary DMA Request – Used for DMA transfers between host and drive
(direction of transfer controlled by DIOR* and DIOW*). Also used in an
asynchronous mode with SDACK*. Drive asserts SDREQ when ready to
transfer or receive data.
(direction of transfer controlled by DIOR* and DIOW*). Also used in an
asynchronous mode with SDACK*. Drive asserts SDREQ when ready to
transfer or receive data.
22
GND
Ground
23
SDIOW*
Secondary I/O Write Strobe – Strobe signal for write functions. Negative edge
enables data from a register or data port of the drive onto the host data bus.
Positive edge latches data at the host.
enables data from a register or data port of the drive onto the host data bus.
Positive edge latches data at the host.
24
GND
Ground
25
SDIOR*
Secondary I/O Read Strobe – Strobe signal for read functions. Negative edge
enables data from a register or data port of the drive onto the host data bus.
Positive edge latches data at the host.
enables data from a register or data port of the drive onto the host data bus.
Positive edge latches data at the host.
26
GND
Ground
27
SDIORDY
Secondary I/O 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.
of any host register access when the drive is not ready to respond to a data
transfer request. High impedance if asserted.
28
NU
Not used (Pull down to ground through 470 ohm resistor)
29
SDDACK*
Secondary DMA Acknowledge – Used by the host to acknowledge data has
been accepted or data is available. Used in response to DMARQ asserted.
been accepted or data is available. Used in response to DMARQ asserted.
30
GND
Ground
31
IRQ15
Interrupt Request 15 – Asserted by drive when it has pending interrupt (PIO
transfer of data to or from the drive to the host).
transfer of data to or from the drive to the host).
32
NC
Not connected