XC68HC705JJ7 Motorola, XC68HC705JJ7 Datasheet - Page 149

• Manufacturer Part Number: XC68HC705JJ7
• Description: MICROCONTROLLER
• Manufacturer: Motorola

9.4.3 SIOP Data Register
MC68HC705JJ7 • MC68HC705JP7 — REV 4
MOTOROLA
Address:
The SIOP data register (SDR) is located at address $000C and serves
as both the transmit and receive data register. Writing to this register will
initiate a message transmission if the node is in master mode. The SIOP
subsystem is not double buffered and any write to this register will
destroy the previous contents. The SDR can be read at any time.
However, if a transfer is in progress the results may be ambiguous.
Writing to the SDR while a transfer is in progress can cause invalid data
to be transmitted and/or received.
bit in the register. This register is not affected by reset.
Reset:
Read:
Write:
done after another transfer has started, the DCOL bit will be set again.
Reset clears the DCOL bit.
1 = Illegal access of the SDR occurred
0 = No illegal access of the SDR detected
$000C
Simple Synchronous Serial Interface
Bit 7
Bit 7
Figure 9-6. SIOP Data Register (SDR)
6
6
5
5
Unaffected by reset
Figure 9-6
4
4
Simple Synchronous Serial Interface
3
3
shows the position of each
2
2
Advance Information
SIOP Registers
1
1
Bit 0
Bit 0
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