sae81c80a Infineon Technologies Corporation, sae81c80a Datasheet - Page 7

• Manufacturer Part Number: sae81c80a
• Description: Cmos Dual-port Ram
• Manufacturer: Infineon Technologies Corporation

SAE 81C80 A
Figure 3
Dual-Port RAM used between Measured-Data Acquisition and the Actuators
Functional Description
Dual-Port RAM
The SAE 81C80A is a 504-byte static RAM simultaneously accessible by two
microcontrollers. The memory locations are selected via a multiplexed address/data bus
and two chip-select inputs. The direction of data transfer is determined by the RD and
WR inputs.
There will be no undefined states when a memory location is concurrently accessed by
two processors, even if they write simultaneously to the same memory location.
Depending on the internal state of the access control and the actual physical sequence,
the value one of the two ports will be stored. Also, if one memory location is read and
written to at the same time, the data will not be mixed, i.e. either the original data or the
new data are read out.
Semiconductor Group
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