Texas Instruments MSP53C391, User Manual

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Pin Assignments and Description
1-4
1.4 Pin Assignments and Description
Figure 1–1 shows the pin assignments for the MSP53C391. Table 1–2 pro-
vides pin functional descriptions. Figure 1–2 shows the pin assignments for
the MSP53C392. Table 1–3 shows the pin functional descriptions.
Figure 1–1. MSP53C391 Pin Assignments
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
DATA2/EOS
DATA1
DATA0
OUT2
OUT1
EOS
R/W
OSC IN
DATA3/BUSY
STROB
IRQ
DAC+
DAC–
V
DD
V
SS
INIT
(TOP VIEW)
MSP53C391
N PACKAGE
Table 1–2. MSP53C391 Terminal Functions
PIN
I/O DESCRIPTION
NAME NO.
I/O DESCRIPTION
DAC+ 13 O D/A output. This output pulses high for positive output values. It remains low
when negative values are output.
DAC– 12 O D/A output. This output pulses high for negative output values. It remains
low when positive values are output.
DATA 0–3 3,2,1,16 I/O Data lines
EOS 6 O End of speech signal. Output high when end of speech is reached.
INIT 9 I Initialize input. When INIT goes low, the clock stops, the MSP53C391 goes into
low-power mode, the program counter is set to zero, and the contents of the
RAM are retained. An INIT pulse of 1
µ
s is sufficient to reset the processor.
IRQ 14 O Negative-edge trigger interrupt request line. Connect to the external inter-
rupt of the master MCU for interrupt mode operation.
OUT 1–2 5,4 O General-purpose output ports used for pin expansion
OSC IN 8 I This signal should be connected to V
SS
.
R/W 7 I Read/write select signal. Set high for read operations or cleared low for
write operations by the master processor.
STROB 15 I Strobe signal for read and write operations. Pulsed low for read or write
operations
V
DD
11 – 5-V nominal supply voltage
V
SS
10 – Ground pin