Memory map of iusc and pld functions, Coldfire (5272) bus, Iusc access – Connect Tech BLUE HEAT/NET SYNC CTIM-00044 User Manual

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Connect Tech Blue Heat/Net Sync User Manual

50 Revision 0.03

Memory Map of IUSC and PLD Functions

ColdFire (5272) Bus:

A ColdFire CS# signal is used to select the entire region, setup with the following attributes…

8K (8192) byte region

16 Bit bus

Use TA# signal to terminate the bus cycle (this places wait state generation in the hands of
the PLD logic).

o CSBR.EBI = 00b

selects 16/32 SRAM/ROM mode

o CSBR.BW = 10b

selects 16 bit bus

o CSOR.WS = 0x1F

selects the use of the TA# signal

o CSOR.BAM = as required

selects size of region

o CSOR.BA = as required

sets 32 bit Base address of the region

o

ColdFire Bus Addresses A0 through A12 are used to “address” all items

A[12]

divides the region into 2 (4096 byte) areas

IUSC Access:

A[12] Must be zero (0).

A[11..9]

Are decoded into 8 functions which access the 4 IUSC devices


A11

A10

A9

IUSC

selected

Function

Notes

0

0

0

0

Register Read/Write

0

0

1

0

Interrupt Acknowledge

Write not allowed [1]

0

1

0

1

Register Read/Write

0

1

1

1

Interrupt Acknowledge

Write not allowed [1]

1

0

0

2

Register Read/Write

1

0

1

2

Interrupt Acknowledge

Write not allowed [1]

1

1

0

3

Register Read/Write

1

1

1

3

Interrupt Acknowledge

Write not allowed [1]

[1] A write to these addresses are ignored, but the ColdFire bus cycle is properly terminated.

A[8] Is “connected” (inverted) to the IUSC S//D pin
0 =

Selects “Serial Controller” registers in the IUSC device.

1 =

Selects “DMA” registers in the IUSC device.


A[7] Is “connected” to the IUSC D//C pin
0 =

Selects Serial “Control” registers

1 = Selects Serial “Data” registers

A write places data into the Transmitter FIFO

A read removes data from the Receiver FIFO


The word “connected” above, is used loosely to mean… The address bit is routed from the
ColdFire bus to the indicated IUSC pin via the logic in the PLD.

A[6] Is not used (set to zero for all operations).

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