IA8237-PDW40C INNOVASIC [InnovASIC, Inc], IA8237-PDW40C Datasheet - Page 2

• Manufacturer Part Number: IA8237-PDW40C
• Description: Programmable DMA Controller
• Manufacturer: INNOVASIC [InnovASIC, Inc]

Programmable DMA Controller
The IA8237 is a programmable direct memory access (DMA) mega-function designed to be
functionally equivalent to the Intel 8237A and Harris 82C37A devices. The A8237 controls data
transfers between memory and peripherals, memory-to-memory transfers, and block memory
initialization. Four independently programmable channels are available, and requests may be
generated via hardware or software.
A block diagram is shown in Figure 1.
Functional Block Diagram
Figure 1
IA8237
MEMW_n
EOP_n
RESET
CS_n
READY
CLK
AEN
ADSTB
MEMR_n
IOR_n
IOW_n
DREQ0_n :
DREQ3_n
HDLA
HRQ_n
DACK0 :
DACK3
ROTATING
CONTROL
ENCODER
PRIORITY
PRIORITY
TIMING
LOGIC
AND
AND
ADDRESS
COMMAND
REQUEST
BASE
DECREMENTOR
MASK
TEMP WORD
COUNT REG
READ BUFFER
Copyright
Customer Specific IC Solutions
COUNT
WORD
BASE
1999, InnovASIC Inc.
16
16
BUFFER
WRITE
INC/DECREMENTOR
CURRENT
ADDRESS
TEMP ADDRESS
READ WRITE BUFFER
INTERNAL DATA
WRITE
MODE
READ
REG
Advanced Information
BUS
CURRENT
STATUS
COUNT
WORD
BUFFER
READ
TEMPORARY
COMMAND
CONTROL
BUFFER
OUTPUT
BUFFER
BUFFER
IO
IO
Page 2 of 4
A4 : A7
DB0 : DB7
A0 : A3
Sheet