User manual

PM_Cmd_VERSION
Description: Returns the firmware version of the Peripheral Microcontroller
Command: 0x03
Data: Don’t Care
Response: 0x00
The current version is 0x00, but future versions will increment this number. This
allows you to determine what functions this particular Peripheral Microcontroller
implements in the event that there are changes in a later version.
PM_Cmd_WD
Description: Set Watchdog Timeout Period
Command: 0x07
Data: See Below
Response: Don’t Care
If the watchdog timer is active, the application must ping the WD input of the
Peripheral Microcontroller with a state change before the watchdog timer expires or
the system will reboot. The watchdog timer is initially disabled.
Data: 0xA6 Disable Watchdog
0x00 18 ms
0x01 36 ms
0x02 72 ms
0x03 144 ms
0x04 288 ms
0x05 576 ms
0x06 1.152 s
0x07 2.304 s
With the exception of 0xA6, all data is masked to use only the lowest 3
bits, i.e. 0xF1 = 0x01.
The watchdog timer uses an independent RC oscillator with a nominal period of 18
ms. This period can vary from 7 ms to 33 ms, so you may want to assume a worst
case situation of 7ms, to keep the watchdog timer from overflowing inadvertently.
dspstak™ 21262sx User Manual Page 23