Texas Instruments ADS1605, Руководство пользователя

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Board-Level Control
2-3 Digital Interface
2.1.3 Resetting the ADS1605 and ADS1606
The ADS1605 and ADS1606 are synchronously reset on the EVM when the
RESET pin is asserted LOW. This can be accomplished by issuing a write
command (WR) via the host system or momentarily depressing switch SW2.
Whichever option is chosen, the reset signal is then synchronized with the
modulator clock and is available for application to the RESET pin of the device.
Alternatively, the user can apply the RESET signal directly via W9.
2.1.4 Out of Range Indication
LED D1 indicates if an out of range (OTR) event has occurred. This LED does
not affect the device’s performance. To clear the LED the device has to be
reset, either manually or via SW2.
2.1.5 Interrupt Source
Some microprocessors only recognize falling edge interrupts; others only
recognize rising edge interrupts while others may be programmed to
recognize either. By using W11, the user can choose either rising edge
interrupts or falling edge interrupts.
2.1.6 Base Address and Chip Select
The EVM can be mapped into a memory location by setting a base address.
There are four possible base addresses for the EVM. The base address is set
by J8. When the logic state of the two external address signals matches the
logic state set-up by the two jumpers on J8 and the access is a valid memory
access, the EVM generates a CS signal for the ADC. This can then be further
qualified as a read cycle or a write (RESET) cycle. An installed jumper is
equivalent to logic 0 on the corresponding address line. An uninstalled jumper
is equivalent to logic 1 on the corresponding address line.
The TMS320C6711 DSK provides two memory spaces for daughter boards.
The two memory-space enables (CE2 and CE3) are buffered versions of the
DSP outputs and are not generated by decode logic on the DSK. The 5−6K
EVM uses CE2 to indicate that the access is valid. This places the daughter
card at an address space beginning at A0000000.
Table 2−4. Memory Space Address
J8
Address selected
1−2 3−4
Address selected
0 0 0xA0000000
0 1 0xA0000004
1 0 0xA0000008
1 1 0xA000000C