Core429-DEV-KIT Actel, Core429-DEV-KIT Datasheet - Page 13

• Manufacturer Part Number: Core429-DEV-KIT
• Description: MCU, MPU & DSP Development Tools ARINC 429 Bus Interface
• Manufacturer: Actel

Specifications of Core429-DEV-KIT

• Processor To Be Evaluated: ProASIC Plus
• Interface Type: RS-232

Label Memory Operation
The label memory is implemented using an internal
memory block. The read address and write address are
generated by internal counters. The read and write
address counters can be reset by setting bit 7 of the
Figure 6 •
To program labels, the CPU first resets the read and write
counters by setting bit 7 of the receive (Rx) control
register to '1'. Then the labels are written to the label
memory. The core will compare the incoming ARINC
word label (bit 1 to 8 of ARINC word) against the labels
contained in the label memory. The contents of the label
memory can be read by reading the label memory
register. While writing to or reading from label memory,
Legacy Operation
In this mode, there is a legacy interface block that
communicates with the CPU interface. When legacy
mode is enabled, the core supports two receive (Rx)
channels and one transmit (Tx) channel only. Legacy
mode is not configurable to support multiple transmit
and receive channels. The purpose of the legacy mode
interface is to replace existing standard products.
Label Memory Diagram
Read Enable
Write Enable
+1
+1
Rx Control Register Bit
Write Address
Read Address
Counter
Counter
Reset
Reset
RADDR
v5.0
WADDR
Label Memory Block
Rx Control Register Bit
Label Enable
receive (Rx) control register to '1'. The write counter
increments each time the label memory register is
written. The read counter increments every time the
label memory register is read.
The label memory operation is shown in
bit 1 of the receive (Rx) control register should be set to
'0'.
To reload the label memory, set bit 7 of the receive (Rx)
control register to '1'. The core will then ignore all
previous labels and new labels can be written to the
label memory.
WDATA
RDATA
Number of Active Labels
(Rx Label Memory Register)
Read Data
(Rx Label Memory Register)
Write Data
ARINC 429 Bus Interface
Figure
6.
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