CS4362A_08 Datasheet, PDF (29/50 Pages) Cirrus Logic – 114 dB, 192 kHz 6-Channel D/A Converter

CS4362A
4.14.1 MAP Auto Increment
The device has MAP (memory address pointer) auto-increment capability enabled by the INCR bit (also
the MSB) of the MAP. If INCR is set to 0, MAP will stay constant for successive I²C writes or reads and
SPI writes. If INCR is set to 1, MAP will auto increment after each byte is written, allowing block reads or
writes of successive registers.
4.14.2 I²C Mode
In the I²C Mode, data is clocked into and out of the bi-directional serial control data line, SDA, by the serial
Control Port clock, SCL (see Figure 17 for the clock to data relationship). There is no CS pin. Pin AD0
enables the user to alter the chip address (001100[AD0][R/W]) and should be tied to VLC or GND, as re-
quired, before powering up the device. If the device ever detects a high-to-low transition on the AD0/CS
pin after power-up, SPI Mode will be selected.
4.14.2.1 I²C Write
To write to the device, follow the procedure below while adhering to the Control Port Switching Specifica-
tions in Section 2.
1. Initiate a START condition to the I²C bus followed by the address byte. The upper 6 bits must be
001100. The seventh bit must match the setting of the AD0 pin, and the eighth must be 0. The eighth
bit of the address byte is the R/W bit.
2. Wait for an acknowledge (ACK) from the part; then write to the memory address pointer, MAP. This
byte points to the register to be written.
3. Wait for an acknowledge (ACK) from the part; then write the desired data to the register pointed to by
the MAP.
4. If the INCR bit (see Section 4.14.1) is set to 1, repeat the previous step until all the desired registers
are written, then initiate a STOP condition to the bus.
5. If the INCR bit is set to 0 and further I²C writes to other registers are desired, it is necessary to initiate
a repeated START condition and follow the procedure detailed from step 1. If no further writes to other
registers are desired, initiate a STOP condition to the bus.
4.14.2.2 I²C Read
To read from the device, follow the procedure below while adhering to the Control Port Switching Speci-
fications.
1. Initiate a START condition to the I²C bus followed by the address byte. The upper 6 bits must be
001100. The seventh bit must match the setting of the AD0 pin, and the eighth must be 1. The eighth
bit of the address byte is the R/W bit.
2. After transmitting an acknowledge (ACK), the device will then transmit the contents of the register
pointed to by the MAP. The MAP register will contain the address of the last register written to the
MAP, or the default address (see Section 4.14.1) if an I²C read is the first operation performed on the
device.
3. Once the device has transmitted the contents of the register pointed to by the MAP, issue an ACK.
4. If the INCR bit is set to 1, the device will continue to transmit the contents of successive registers. Con-
tinue providing a clock and issue an ACK after each byte until all the desired registers are read; then
initiate a STOP condition to the bus.
5. If the INCR bit is set to 0 and further I²C reads from other registers are desired, it is necessary to initiate
a repeated START condition and follow the procedure detailed from steps 1 and 2 from the I²C Write
DS617F1
29