isp1161bm NXP Semiconductors, isp1161bm Datasheet - Page 88

• Manufacturer Part Number: isp1161bm
• Description: Isp1161 Full-speed Universal Serial Bus Single-chip Host And Device Controller
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 09567
Product data
12.2 8237 compatible mode
Table 71:
The 8237 compatible DMA mode is selected by clearing bit DAKOLY in the
DcHardwareConfiguration register (see
shown in
Table 72:
The DMA subsystem of an IBM compatible PC is based on the Intel 8237 DMA
controller. It operates as a ‘fly-by’ DMA controller: the data is not stored in the DMA
controller, but it is transferred between an I/O port and a memory address. A typical
example of ISP1161’s DC in 8237 compatible DMA mode is given in
The 8237 has two control signals for each DMA channel: DREQ (DMA Request) and
DACK (DMA Acknowledge). General control signals are HRQ (Hold Request) and
HLDA (Hold Acknowledge). The bus operation is controlled via MEMR (Memory
read), MEMW (Memory write), IOR (I/O read) and IOW (I/O write).
Symbol
DREQ2
DACK2
EOT
RD
WR
Fig 41. ISP1161’s device controller in 8237 compatible DMA mode.
Endpoint
identifier
10
11
12
13
14
Table
Description
DC’s DMA request
DC’s DMA acknowledge I
end of transfer
read strobe
write strobe
Endpoint selection for DMA transfer
8237 compatible mode: pin functions
CONTROLLER
ISP1161
DEVICE
72.
Rev. 02 — 13 December 2002
D0 to D15
DREQ2
DACK2
EPIDX[3:0]
WR
RD
1011
1100
1101
1110
1111
Full-speed USB single-chip host and device controller
RAM
I/O
O
I
I
I
Table
Function
ISP1161’s DC requests a DMA transfer
DMA controller confirms the transfer
DMA controller terminates the transfer
instructs ISP1161’s DC to put data on the bus
instructs ISP1161’s DC to get data from the bus
MEMR
MEMW
DREQ
DACK
IOR
IOW
EPDIR = 0
OUT: read
OUT: read
OUT: read
OUT: read
OUT: read
CONTROLLER
83). The pin functions for this mode are
…continued
DMA
8237
Transfer direction
HLDA
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
HRQ
HRQ
HLDA
ISP1161
EPDIR = 1
CPU
Figure
004aaa009
IN: write
IN: write
IN: write
IN: write
IN: write
41.
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