Iic Operation Reservation Adapter Command Register (Iccmd); Iic Operation Reservation Adapter; Restrictions On Accessing Iic Registers - Renesas H8S/2158 User Manual

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Section 17 I C Bus Interface (IIC)

17.3.14 IIC Operation Reservation Adapter Command Register (ICCMD)

ICCMD is an 8-bit readable/writable register that specifies an IIC operation reservation adapter
command. When the reserved operation is completed, ICCMD may be automatically modified to
contain the next related command. For details on commands and operations, see section 17.4, IIC
Operation Reservation Adapter.
When the ICXE bit in ICCRX is set to 1, ICCMD is automatically set to H'A0. When the ICXE bit
in ICCRX is cleared to 0, ICCMD is cleared to H'00.
If a value not defined as an operation reservation command is written to ICCMD when the ICXE
bit is set to 1, the CERR bit in ICSRB is set to 1 and a CREQ interrupt request is generated. In this
case, ICCMD is reset to H'A0. When the ICXE bit is cleared to 0, no value can be written to
ICCMD.
17.4

IIC Operation Reservation Adapter

17.4.1

Restrictions on Accessing IIC Registers

There are restrictions when accessing registers other than those related to the IIC operation
reservation adapter when the IIC operation reservation adapter is enabled (ICXE = 1 in ICCRX),
as shown in table 17.5.
Rev. 3.00 Jan 25, 2006 page 510 of 872
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