I2C BUS INTERFACE
2
I C BUS INTERFACE (Cont’d)
INTERRUPT VECTOR REGISTER (I2CIVR)
R249 - Read / Write
Register Page: 20 (I2C_0) or 22 (I2C_1)
Reset Value: Undefined
(DMA between peripheral and Register file), this
register has no meaning.
See Section 10.8.6.1 for more details on the use
of this register.
7
0
Bit 0 = RPS Receiver DMA Memory Pointer Selec-
tor.
If memory has been selected for DMA transfer
(I2CRDC.RF/MEM = 0) then:
V7
V6
V5
V4
V3 EV2 EV1
0
0: Select ISR register for Receiver DMA transfer
address extension.
1: Select DMASR register for Receiver DMA trans-
fer address extension.
Bits 7:3 = V[7:3] Interrupt Vector Base Address.
User programmable interrupt vector bits. These
are the five more significant bits of the interrupt
vector base address. They must be set before en-
abling the interrupt features.
RECEIVER DMA TRANSACTION COUNTER
REGISTER (I2CRDC)
Bits 2:1 = EV[2:1] Encoded Interrupt Source.
These Read-Only bits are set by hardware accord-
ing to the interrupt source:
R251 - Read / Write
Register Page: 20 (I2C_0) or 22 (I2C_1)
Reset Value: Undefined
– 01: error condition detected
– 10: data received
7
0
– 11: peripheral ready to transmit
RC7 RC6 RC5 RC4 RC3 RC2 RC1 RF/MEM
Bit 0 = Reserved.
Bits 7:1 = RC[7:1] Receiver DMA Counter Pointer.
I2CRDC contains the address of the pointer (in the
Register File) of the DMA receiver transaction
counter when the DMA between Peripheral and
Memory Space is selected. Otherwise (DMA be-
tween Peripheral and Register File), this register
points to a pair of registers that are used as DMA
Address register and DMA Transaction Counter.
See Section 10.8.6.1 and Section 10.8.6.2 for
more details on the use of this register.
Forced by hardware to 0.
RECEIVER DMA SOURCE ADDRESS POINTER
REGISTER (I2CRDAP)
R250 - Read / Write
Register Page: 20 (I2C_0) or 22 (I2C_1)
Reset Value: Undefined
7
0
RA7 RA6 RA5 RA4 RA3 RA2 RA1
RPS
Bit 0 = RF/MEM Receiver Register File/ Memory
Selector.
0: DMA towards Memory
Bits 7:1 = RA[7:1] Receiver DMA Address Pointer.
I2CRDAP contains the address of the pointer (in
the Register File) of the Receiver DMA data
source when the DMA is selected between the
peripheral and the Memory Space. Otherwise,
1: DMA towards Register file
279/426
9
STMICROELECTRONICS [ ST ]
