tmp88f846ug TOSHIBA Semiconductor CORPORATION, tmp88f846ug Datasheet - Page 200

• Manufacturer Part Number: tmp88f846ug
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

19.3 Serial PROM Mode Setting
19. Serial PROM Mode
19.3 Serial PROM Mode Setting
Table 19-3 Pin Function in the Serial PROM Mode
19.3.1 Serial PROM Mode Control Pins
19.3.2 Pin Function
TXD
BOOT/RXD
RESET
TEST
VDD, AVDD
VSS, AVSS
VAREF
I/O ports except
P45, P44
Note: The BOOT pin is shared with the UART communication pin (RXD pin) in the serial PROM mode. This pin is used as UART
Note 1: During on-board programming with other parts mounted on a user board, be careful no to affect these communication
Note 2: TXD port is set a open-drain port in seriarl PROM mode and it needs pull-up resistor.
(Serial PROM Mode)
the serial PROM mode.
Pin Name
To execute on-board programming, activate the serial PROM mode. Table 19-2 shows pin setting to activate
communication pin after activating serial PROM mode
In the serial PROM mode, TXD (P45) and RXD (P44) are used as a serial interface pin.
control pins.
Output
Input/Input
Input
Input
Power
supply
Power
supply
Power
supply
I/O
Output
Input/
Table 19-2 Serial PROM Mode Setting
Serial data output
Serial PROM mode control/Serial data input
Serial PROM mode control
Fixed to high
4.5 to 5.5 V
0 V
Leave open or apply input reference voltage.
These ports are in the high-impedance state in the serial PROM mode. The input level is fixed to
the port inputs with a hardware feature to prevent overlap current. (The port inputs are invalid.) To
make the port inputs valid, set the pin of the SPCR register to “1” by the RAM loader control pro-
gram.
BOOT/RXD pin
RESET
TEST pin
Pin
pin
Page 190
Function
Setting
High
High
(Note 3)
(Note 1)
P45
P44
RESET
TEST
(MCU Mode)
Pin Name
TMP88F846UG