RBIL61 - PORT 040A-043F - Intel 82378ZB embedded DMA controller

PORTIBM PC Portable (uses same BIOS as XT) 040A-043F - Intel 82378ZB embedded DMAsee Direct Memory Access controller
Range:	relocatable via Relocation Base Address register (see #01075)
SeeAlso: PORTIBM PC Portable (uses same BIOS as XT) 0401h"EISA(Enhanced Industry-Standard Architecture) A 32-bit superset of the IBMInternational Busiuness Machines ATIBM PC AT's expansion bus (which is now known as the ISA or Industry-Standard Architecture bus).",#01064,#01075

040A  R-  scatter/gather interrupt status (see #P0887)
040B  -W  DMA1 extended mode
0410  -W  CH0 scatter/gather command (see #P0888)
0411  -W  CH1 scatter/gather command
0412  -W  CH2 scatter/gather command
0413  -W  CH3 scatter/gather command
0414  -W  CH4 scatter/gather command
0415  -W  CH5 scatter/gather command
0416  -W  CH6 scatter/gather command
0417  -W  CH7 scatter/gather command (see #P0888)
0418  R-  CH0 scatter/gather status (see #P0889)
0419  R-  CH1 scatter/gather status
041A  R-  CH2 scatter/gather status
041B  R-  CH3 scatter/gather status
041C  R-  CH4 scatter/gather status
041D  R-  CH5 scatter/gather status
041E  R-  CH6 scatter/gather status
041F  R-  CH7 scatter/gather status (see #P0889)
0420d RW  CH0 scatter/gather descriptor table address
0424d RW  CH1 scatter/gather descriptor table address
0428d RW  CH2 scatter/gather descriptor table address
042Cd RW  CH3 scatter/gather descriptor table address
0430d RW  CH4 scatter/gather descriptor table address
0434d RW  CH5 scatter/gather descriptor table address
0438d RW  CH6 scatter/gather descriptor table address
043Cd RW  CH7 scatter/gather descriptor table address


(Table P0887)
Call Intel 82378ZB Scatter/GatherA technique in which the contiguous data of a disk sector or sectors is transferred to or from multiple non-contiguous areas of memory.  When reading into multiple areas of memory, this is called a scatter-read; the opposing operation is called gather-write. Interrupt Status Register with:
 7	channel 7 has interrupt due to S/G transfer
 ...
 0	channel 0 has interrupt due to S/G transfer
SeeAlso: #P0888,#P0889


Bitfields for Intel 82378ZB Scatter/GatherA technique in which the contiguous data of a disk sector or sectors is transferred to or from multiple non-contiguous areas of memory.  When reading into multiple areas of memory, this is called a scatter-read; the opposing operation is called gather-write. Command Register:
Bit(s)	Description	(Table P0888)
  7	select last-buffer termination type
	=0 assert IRQ13 on completion
	=1 assert EOP on completion
 6	enable bit 7 termination-type selection
 5-2	reserved (0)
 1-0	scatter-gather command
	00 none
	01 start S/G command
	10 stop S/G command
	11 reserved
SeeAlso: #P0887,#P0889,#01075


Bitfields for Intel 82378ZB Scatter/GatherA technique in which the contiguous data of a disk sector or sectors is transferred to or from multiple non-contiguous areas of memory.  When reading into multiple areas of memory, this is called a scatter-read; the opposing operation is called gather-write. Status Register:
Bit(s)	Description	(Table P0889)
 7	no next link
 6	reserved
 5	issue IRQ13 instead of EOP at end of last buffer
 4	reserved
 3	scatter/gather Base Register status
	=1 buffer link has been loaded
	=0 empty
 2	scatter/gather Current Register status
	=1 buffer link has been loaded
	=0 empty
 1	reserved
 0	scatter/gather is active
SeeAlso: #P0888