MA31753

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5.4 AREA 1 AND 2 PB, PS AND AS

These readable and writable registers store the Page Bank, Processor and Address State information to be used when

accessing areas 1 and 2. When areas are defined within IO space, PB, PS and AS are set to zero.

5.5 TRANSFER INTERVAL

This readable and writable register gives the number of CLK cycles between each DMA request generated during area to

area transfers. The number entered as the interval value corresponds to a clock cycle interval increasing by 32 as follows:

0

=>

- (externally triggered DMA requests)

1

=>

0 (continuous DMA requests until the block is completed.

2=>

32

3=>

64

4=>

96

..

..

..

14

=>

416

15

=>

448

This function is valid only for transfers on channels 0 and 1. Channels 2 and 3 work ony only on externally triggered requests.

5.6 CONFIGURATION WORD

The DMA controller snoops the system address bus for the XIO address 0x8410. When this appears, the DMA stores the data

bus (qualified by DSN low) in an internal copy of the CPU configuration word.

OIN

PB0

PS0

AS0

PB3

PS3

AS3

D0

D15

Interval

D0

D15