IDT Device Controller
Theory of Operation
79RC32438 User Reference Manual
6 - 2
November 4, 2002
Notes
Theory of Operation
The following memory and peripheral bus signals are managed by the device controller during device
transactions:
–
MADDR[25:0] (address bus, MADDR[21:0] directly available as I/O pins, MADDR[25:22] are
GPIO alternate functions)
–
MDATA[15:0] (data bus)
–
OEN (output enable, may be used as Intel style read signal)
–
BWEN[1:0] (byte write enables, may be used as Intel style write signals)
–
RWN (Motorola style read/write signal)
–
CSN[5:0] (chip selects)
–
WAITACKN (configurable as Intel style wait signal or Motorola style transfer acknowledge signal)
–
BOEN (external data bus buffer output enable)
–
BDIRN (external data bus buffer direction).
All memory and peripheral bus transactions are synchronous to the master clock (EXTCLK). Therefore,
all of the timing parameters in the Device Control (DEVxC) and Device Timing Control (DEVxTC) registers
are in terms of master clock (EXTCLK) clock cycles.
0x01_0024
DEV2MASK
Device 2 Mask
32-bit
0x01_0028
DEV2C
Device 2 Control
32-bit
0x01_002C
DEV2TC
Device 2 Timing control
32-bit
0x01_0030
DEV3BASE
Device 3 Base
32-bit
0x01_0034
DEV3MASK
Device 3 Mask
32-bit
0x01_0038
DEV3C
Device 3 Control
32-bit
0x01_003C
DEV3TC
Device 3 Timing control
32-bit
0x01_0040
DEV4BASE
Device 4 Base
32-bit
0x01_0044
DEV4MASK
Device 4 Mask
32-bit
0x01_0048
DEV4C
Device 4 Control
32-bit
0x01_004C
DEV4TC
Device 4 Timing control
32-bit
0x01_0050
DEV5BASE
Device 5 Base
32-bit
0x01_0054
DEV5MASK
Device 5 Mask
32-bit
0x01_0058
DEV5C
Device 5 Control
32-bit
0x01_005C
DEV5TC
Device 5 Timing control
32-bit
0x01_0060
BTCS
Bus Timer Control and Status
32-bit
0x01_0064
BTCOMPARE
Bus Transaction Timer Compare
32-bit
0x01_0068
BTADDR
Bus Transaction Timer Address
32-bit
0x01_006C
DEVDACS
Device Decoupled Access Control and
Status
32-bit
0x01_0070
DEVDAA
Device Decoupled Access Address
32-bit
0x01_0074
DEVDAD
Device Decoupled Access Data
32-bit
0x01_0078 through 0x01_7FFF
Reserved
1.
The address of the register is equal to the register offset added to the base value of 0x1800_0000.
Register Offset
1
Register Name
Register Function
Size
Table 6.1 Device Controller Register Map