Table 34, Atmega163(l), Table 34. status codes for slave receiver mode – Rainbow Electronics ATmega163L User Manual
Page 81

ATmega163(L)
81
brne
ERROR
in
r16, TWDR
; Input received data from TWDR.
nop
;<do something with received data>
ldi
r16, (1<<TWINT) | (1<<TWSTO) | (1<<TWEN)
out
TWCR, r16
; Send STOP signal
Table 34. Status Codes for Slave Receiver Mode
Status code
(TWSR)
Status of the 2-wire Serial Bus
and 2-wire Serial Interface hard-
ware
Application software response
Next action taken by 2-wire Serial Interface hardtware
To/from TWDR
To TWCR
STA
STO
TWIN
T
TWE
A
$60
Own SLA+W has been received;
ACK has been returned
No TWDR action or
No TWDR action
X
X
0
0
1
1
0
1
Data byte will be received and NOT ACK will be
returned
Data byte will be received and ACK will be returned
$68
Arbitration lost in SLA+R/W as
master; own SLA+W has been
received; ACK has been returned
No TWDR action or
No TWDR action
X
X
0
0
1
1
0
1
Data byte will be received and NOT ACK will be
returned
Data byte will be received and ACK will be returned
$70
General call address has been
received; ACK has been returned
No TWDR action or
No TWDR action
X
X
0
0
1
1
0
1
Data byte will be received and NOT ACK will be
returned
Data byte will be received and ACK will be returned
$78
Arbitration lost in SLA+R/W as
master; General call address has
been received; ACK has been
returned
No TWDR action or
No TWDR action
X
X
0
0
1
1
0
1
Data byte will be received and NOT ACK will be
returned
Data byte will be received and ACK will be returned
$80
Previously addressed with own
SLA+W; data has been received;
ACK has been returned
Read data byte or
Read data byte
X
X
0
0
1
1
0
1
Data byte will be received and NOT ACK will be
returned
Data byte will be received and ACK will be returned
$88
Previously addressed with own
SLA+W; data has been received;
NOT ACK has been returned
Read data byte or
Read data byte or
Read data byte or
Read data byte
0
0
1
1
0
0
0
0
1
1
1
1
0
1
0
1
Switched to the not addressed slave mode;
no recognition of own SLA or GCA
Switched to the not addressed slave mode;
own SLA will be recognized;
GCA will be recognized if TWGCE = ‘1’
Switched to the not addressed slave mode;
no recognition of own SLA or GCA;
a START condition will be transmitted when the bus
becomes free
Switched to the not addressed slave mode;
own SLA will be recognized;
GCA will be recognized if TWGCE = ‘1’;
a START condition will be transmitted when the bus
becomes free
$90
Previously addressed with
general call; data has been re-
ceived; ACK has been returned
Read data byte or
Read data byte
X
X
0
0
1
1
0
1
Data byte will be received and NOT ACK will be
returned
Data byte will be received and ACK will be returned
$98
Previously addressed with
general call; data has been
received; NOT ACK has been
returned
Read data byte or
Read data byte or
Read data byte or
Read data byte
0
0
1
1
0
0
0
0
1
1
1
1
0
1
0
1
Switched to the not addressed slave mode;
no recognition of own SLA or GCA
Switched to the not addressed slave mode;
own SLA will be recognized;
GCA will be recognized if TWGCE = ‘1’
Switched to the not addressed slave mode;
no recognition of own SLA or GCA;
a START condition will be transmitted when the bus
becomes free
Switched to the not addressed slave mode;
own SLA will be recognized;
GCA will be recognized if TWGCE = ‘1’;
a START condition will be transmitted when the bus
becomes free