Tadpole SPARCbook 3 series, Reference Manual

Page: 186 / 216

12-6
Microcontroller Subsystem
Command Set
12.2 Command Set
The microcontroller command set is organized into several functional
groups. The command structure is the same for all groups.
12.2.1 Command synchronization
The administartion of the host-microcontroller link must be single
threaded; only one data exchange may be active at any time. The sync
command (0x00) can be used to bring the microntroller and host into phase.
This allows the data stream from the microcontroller to be discarded until
the synchronizing byte is found.
{how do I know when I have received the synchronizing byte}
12.2.2 System Information Commands
Opcode Command Argument Returned Function
0x01 Read Serial
Number none ack + 4 bytes The Unit Serial Number is represented by a four byte value held
in EEPROM. These are returned in the order msb...lsb.
0x02 Read Ethernet
Address none ack + 6 bytes The Ethernet Hardware Address for the unit is represented by six
byte values, held in EEPROM. These are returned in ordermsb ..
lsb.
0x03 Read
Hardware
Version none ack +2 bytes The Hardware Version is held in two EEPROM byte values.
These are returned in order major .. minor.
0x04 Read
Microcontroller
Version none ack + 2 bytes The Microcontroller Version is hardwired into the
microcontroller firmware. It is described by two byte values,
returned in order major .. minor.
0x05 Read Max
Temperature none ack + 1 byte The Maximum Recorded temperature is held in EEPROM as a
byte value. This value is returned.
0x06 Read Min
Temperature none ack + 1 byte The Minimum Recorded temperature is held in EEPROM as a
byte value. This value is returned.
0x07 Read Current
Temperature none ack + 1 byte The Current Temperature is read from the unit temperature
sensor and returned as a byte value.
0x08 Read System
Variant none ack + 4 bytes System variant information is held in EEPROM as four byte
values. This includes, for example, non-US keyboard and base
board type. The encoding of these values is understood by both
microcontroller and host system software.
0x09 Read
Power-on
Cycles ack + 4 bytes This command returns the number of times that the unit has been
powered-on. This value is held in EEPROM as a four byte value
which are returned in order msb...lsb. Assuming an average of
ten power-on cycles per day, this value will overflow in just
around eighteen years.
Table 12-1 System Information Command Summary
S3GX_TRMBook Page 6 Friday, September 19, 1997 11:39 am