ST7263-EMU2 STMicroelectronics, ST7263-EMU2 Datasheet - Page 80

• Manufacturer Part Number: ST7263-EMU2
• Description: MCU, MPU & DSP Development Tools ST7 Emulator Board
• Manufacturer: STMicroelectronics

Specifications of ST7263-EMU2

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ST7263
I²C BUS INTERFACE (Cont’d)
I²C STATUS REGISTER 1 (SR1)
Read Only
Reset Value: 0000 0000 (00h)
Bit 7 = EVF Event flag.
This bit is set by hardware as soon as an event oc-
curs. It is cleared by software reading SR2 register
in case of error event or as described in
is also cleared by hardware when the interface is
disabled (PE=0).
0: No event
1: One of the following events has occurred:
Bit 6 = Reserved. Forced to 0 by hardware.
Bit 5 = TRA Transmitter/Receiver.
When BTF is set, TRA=1 if a data byte has been
transmitted. It is cleared automatically when BTF
is cleared. It is also cleared by hardware after de-
tection of Stop condition (STOPF=1), loss of bus
arbitration (ARLO=1) or when the interface is disa-
bled (PE=0).
0: Data byte received (if BTF=1)
1: Data byte transmitted
Bit 4 = BUSY Bus busy .
This bit is set by hardware on detection of a Start
condition and cleared by hardware on detection of
a Stop condition. It indicates a communication in
progress on the bus. This information is still updat-
ed when the interface is disabled (PE=0).
0: No communication on the bus
1: Communication ongoing on the bus
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EVF
– BTF=1 (Byte received or transmitted)
– ADSL=1 (Address matched in Slave mode
– SB=1 (Start condition generated in Master
– AF=1 (No acknowledge received after byte
– STOPF=1 (Stop condition detected in Slave
– ARLO=1 (Arbitration lost in Master mode)
– BERR=1 (Bus error, misplaced Start or Stop
– Address byte successfully transmitted in Mas-
7
while ACK=1)
mode)
transmission)
mode)
condition detected)
ter mode.
0
TRA
BUSY
BTF
ADSL
M/SL
Figure
SB
0
3. It
Bit 3 = BTF Byte transfer finished.
This bit is set by hardware as soon as a byte is cor-
rectly received or transmitted with interrupt gener-
ation if ITE=1. It is cleared by software reading
SR1 register followed by a read or write of DR reg-
ister. It is also cleared by hardware when the inter-
face is disabled (PE=0).
– Following a byte transmission, this bit is set after
– Following a byte reception, this bit is set after
The SCL line is held low while BTF=1.
0: Byte transfer not done
1: Byte transfer succeeded
Bit 2 = ADSL Address matched (Slave mode).
This bit is set by hardware as soon as the received
slave address matched with the OAR register con-
tent or a general call is recognized. An interrupt is
generated if ITE=1. It is cleared by software read-
ing SR1 register or by hardware when the inter-
face is disabled (PE=0).
The SCL line is held low while ADSL=1.
0: Address mismatched or not received
1: Received address matched
Bit 1 = M/SL Master/Slave.
This bit is set by hardware as soon as the interface
is in Master mode (writing START=1). It is cleared
by hardware after detecting a Stop condition on
the bus or a loss of arbitration (ARLO=1). It is also
cleared when the interface is disabled (PE=0).
0: Slave mode
1: Master mode
Bit 0 = SB Start bit (Master mode).
This bit is set by hardware as soon as the Start
condition
START=1). An interrupt is generated if ITE=1. It is
cleared by software reading SR1 register followed
by writing the address byte in DR register. It is also
cleared by hardware when the interface is disa-
bled (PE=0).
0: No Start condition
1: Start condition generated
reception of the acknowledge clock pulse. In
case an address byte is sent, this bit is set only
after the EV6 event (See
cleared by reading SR1 register followed by writ-
ing the next byte in DR register.
transmission of the acknowledge clock pulse if
ACK=1. BTF is cleared by reading SR1 register
followed by reading the byte from DR register.
is
generated
Figure
(following
3). BTF is
a
write