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21.4.4
Pin Configuration
The flash memory is controlled by means of the pins shown in table 21.3.
Table 21.3 Flash Memory Pins
Pin Name
Abbreviation
I/O
Function
Reset
5(6
Input
Reset
Mode 1
MD1
Input
Sets MCU operating mode
Mode 0
MD0
Input
Sets MCU operating mode
Port 92
P92
Input
Sets MCU operating mode when MD1 = MD0 = 0
Port 91
P91
Input
Sets MCU operating mode when MD1 = MD0 = 0
Port 90
P90
Input
Sets MCU operating mode when MD1 = MD0 = 0
Transmit data
TxD1
Output
Serial transmit data output
Receive data
RxD1
Input
Serial receive data input
21.4.5
Register Configuration
The registers used to control the on-chip flash memory when enabled are shown in table 21.4.
In order for these registers to be accessed, the FLSHE bit must be set to 1 in STCR.
Table 21.4 Flash Memory Registers
Register Name
Abbreviation R/W
Initial Value
Address*
1
Flash memory control register 1
FLMCR1*
5
R/W*
3
H'00
H'FF80*
2
Flash memory control register 2
FLMCR2*
5
R/W*
3
H'00*
4
H'FF81*
2
Erase block register 1
EBR1*
5
R/W*
3
H'00*
4
H'FF82*
2
Erase block register 2
EBR2*
5
R/W*
3
H'00*
4
H'FF83*
2
Serial/timer control register
STCR
R/W
H'00
H'FFC3
Notes: 1. Lower 16 bits of the address.
2. Flash memory registers share addresses with other registers. Register selection is
performed by the FLSHE bit in the serial/timer control register (STCR).
3. In modes in which the on-chip flash memory is disabled, a read will return H'00, and
writes are invalid.
4. The SWE bit in FLMCR1 is not set, these registers are initialized to H'00.
5. FLMCR1, FLMCR2, EBR1, and EBR2 are 8-bit registers. Only byte accesses are valid
for these registers, the access requiring 2 states. These registers are used only in the
flash memory version. In the mask ROM version, a read at any of these addresses will
return an undefined value, and writes are invalid.