tmp86c408idmg TOSHIBA Semiconductor CORPORATION, tmp86c408idmg Datasheet - Page 123

• Manufacturer Part Number: tmp86c408idmg
• Description: Cmos 8-bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

(0028H)
(0029H)
11.2.2 SEI Status Register (SESR)
11.2.3 SEI Data Register (SEDR)
SESR
SEDR
is initiated by writing to this SEDR register. If the master device needs to write to the SEDR register after
transfer began, always check to see by means of an interrupt or by polling that the SEF flag (SESR<SEF>) is
set, before writing to the SEDR register.
The SEI Data Register (SEDR) is used to send and receive data. When the SEI is set for master, data transfer
SED7
SEF
7
7
WCOL
SOVF
#1
#2
#3
SEF
(2)
SER bit has no effect. The maximum transfer rate is fc/4.
The SEF flag is automatically set at completion of transfer. The SEF flag thus set is automatically cleared by
reading the SESR register and accessing the SEDR register.
The WCOL flag is automatically set by a write to the SEDR register while transfer is in progress. Writing to
the SEDR register during transfer has no effect. The WCOL flag thus set is automatically cleared by reading
the SESR register and accessing the SEDR register. No interrupts are generated for reasons that the WCOL
flag is set.
During master mode:
This bit does not function; its data when read is “0”.
During slave mode:
The SOVF flag is automatically set when the device finishes reading the next data while the SEF flag is set.
The SOVF flag thus set is automatically cleared by reading the SESR register and accessing the SEDR reg-
ister. The SOVF flag also is cleared by a switchover to master mode. No interrupts are generated for rea-
sons that the SOVF flag is set.
WCOL
Slave mode
When the SEI is operating as a slave, the serial clock is input from the master and the setting of the
Note: Take note of the following relationship between the serial clock speed and fc on the master side:
SED6
6
6
Transfer-finished flag
Write collision error flag
Overflow error flag (slave)
Example) 15.625 kbps < Transfer rate < 4 Mbps (fc = 16 MHz at V
SOVF
SED5
15.625 kbps < Transfer rate < fc/4 bps
5
5
15.625 kbps < Transfer rate < 2 Mbps (fc = 8 MHz at V
SED4
#1
4
−
4
#2
#3
SED3
3
3
Page 113
SED2
2
2
0: Transfer in progress
1: Transfer completed
0: No write collision error occurred
1: Write collision error occurred
0: No overflow occurred
1: Overflow occurred
SED1
1
1
SED0
0
0
(Initial value: 0000 ****)
R/W (Initial value: 0000 0000)
DD
DD
= 4.5 to 5.5 V)
= 2.7 to 5.5 V)
TMP86C408IDMG
Read
only