STR910FM32X6T STMICROELECTRONICS [STMicroelectronics], STR910FM32X6T Datasheet - Page 31

• Manufacturer Part Number: STR910FM32X6T
• Description: ARM966E-S 16/32-Bit Flash MCU with Ethernet, USB, CAN, AC Motor Control, 4 Timers, ADC, RTC, DMA
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

STR91xF
●
Figure 4.
To use all 24 address bits, the following applies: 8 bits of lowest-order data and 8 bits of
lowest-order address are multiplexed on port 8. On port 9, 8-bits of mid-order address are
multiplexed with 8 bits of data, but these 8 data values are always at logic zero on this port
during a write operation, and these 8 data bits are ignored during a read operation. An
external latch device (such as a ‘373 latch) is needed to de-multiplex the mid-order 8
address bits that are generated on port 8. Port 7 outputs the 8 highest-order address
signals directly (not multiplexed). The output signal on pin EMI_ALE is used to demultiplex
the signals on ports 8 and 9, and the polarity of EMI_ALE is programmable. The output
signal on pin EMI_BWR_WRLn is the data write strobe, and the output on pin EMI_RDn is
the data read strobe.
only require 8 bits of address on an 8-bit multiplexed address/data bus, and have simple
read, write, and latch inputs as shown in
8-bit non-multiplexed data mode
of address are output on ports 7 and 9. The output signal on pin EMI_BWR_BWLn is the
data write strobe and the output on pin EMI_RDn is the data read strobe.
EMI 16-bit multiplexed connection example
STR91xx
EMI_BWR_WRLn
(1)
EMI_WRHn
EMI_AD15
EMI_AD14
EMI_AD13
EMI_AD12
EMI_AD11
EMI_AD10
EMI_CS3n
EMI_CS2n
EMI_CS1n
EMI_CS0n
EMI_AD9
EMI_AD8
EMI_AD7
EMI_AD6
EMI_AD5
EMI_AD4
EMI_AD3
EMI_AD2
EMI_AD1
EMI_AD0
EMI_RDn
EMI_ALE
EMI_A22
EMI_A21
EMI_A20
EMI_A19
EMI_A18
EMI_A17
EMI_A16
EMI_A23
P7.7
P7.6
P7.5
P7.4
P7.3
P7.2
P7.1
P7.0
P9.7
P9.6
P9.5
P9.4
P9.3
P9.2
P9.1
P9.0
P8.7
P8.6
P8.5
P8.4
P8.3
P8.2
P8.1
P8.0
(Figure
Figure 5
6): Eight bits of data are on port 8, while 16 bits
CHIP_SELECT
WRITE_HIGH_BYTE
WRITE_LOW_BYTE
READ
ADDR_LATCH
A23
A22
A21
A20
A19
A18
A17
A16
AD15
AD14
AD13
AD12
AD11
AD10
AD9
AD8
AD7
AD6
AD5
AD4
AD3
AD2
AD1
AD0
DEVICE
16-BIT
Functional overview
31/72