MAX1040 Datasheet, PDF (30/44 Pages) Maxim Integrated Products – 10-Bit, Multichannel ADCs/DACs with FIFO, Temperature Sensing, and GPIO Ports

10-Bit, Multichannel ADCs/DACs with FIFO,
Temperature Sensing, and GPIO Ports
See Tables 13 and 14. The register bits are updated
after the last CS rising edge. All GPIOs default to inputs
upon power-up.
The data in the register controls the function of each
GPIO, as shown in Tables 13, 14, and 16.
GPIO Write
Write the command byte 00000010 to indicate a GPIO
write operation. The eight SCLK cycles following the
command byte load data from DIN into the GPIO write
register in the MAX1042/MAX1043/MAX1048/MAX1049.
See Tables 14 and 15. The register bits are updated
after the last CS rising edge.
GPIO Read
Write the command byte 00000001 to indicate a GPIO
read operation. The eight SCLK cycles following the
command byte transfer the state of the GPIOs to DOUT
in the MAX1042/MAX1043/MAX1048/MAX1049. See
Table 16.
DAC Serial Interface
Write a command byte 0001XXXX to the DAC select
register to indicate the word to follow is written to the
DAC serial interface, as detailed in Tables 1, 10, 17, and
18. Write the next 16 bits to the DAC interface register,
as shown in Tables 17 and 18. Following the high-to-low
transition of CS, the data is shifted synchronously and
latched into the input register on each falling edge of
SCLK. Each word is 16 bits. The first 4 bits are the con-
trol bits, followed by 10 data bits (MSB first), followed by
2 sub-bits. See Figures 9–12 for DAC timing specifica-
tions.
If CS goes high prior to completing 16 SCLK cycles,
the command is discarded. To initiate a new transfer,
drive CS low again.
For example, writing the DAC serial interface word 1111
0000 and 0011 0100 disconnects DAC outputs 2 and 3
and forces them to a high-impedance state. DAC out-
puts 0 and 1 remain in their previous state.
Table 13. MAX1042/MAX1043/MAX1048/MAX1049 GPIO Configuration
DATA PIN
DIN
DOUT
GPIO COMMAND BYTE
00000011
00000000
GPIOC1
0
GPIOC0
0
DATA BYTE
GPIOA1 GPIOA0
0
0
XXXX
0000
Table 14. MAX1042/MAX1043/MAX1048/MAX1049 GPIO Write
DATA PIN
GPIO COMMAND BYTE
DATA BYTE
DIN
0 0 0 0 0 0 1 0 GPIOC1 GPIOC0 GPIOA1 GPIOA0 X X X X
DOUT
00000000
0
0
0
0
0 000
Table 15. GPIO-Mode Control
CONFIGURATION
BIT
1
1
0
WRITE
BIT
1
0
1
OUTPUT
STATE
1
0
Tri-state
0
0
0
GPIO
FUNCTION
Output
Output
Input
Pulldown
(open drain)
Table 16. MAX1042/MAX1043/MAX1048/MAX1049 GPIO Read
DATA PIN
GPIO COMMAND BYTE
DIN
00000001 X X X X
DOUT
00000000 0 0 0 0
DATA BYTE
X
X
GPIOC1
GPIOC0
X
GPIOA1
30 ______________________________________________________________________________________
X
GPIOA0