Tadpole SPARCbook 3 series, Reference Manual

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Microcontroller Subsystem
12-15
Command Set
12.2.5 Block Transfer Commands
This gorup of commands handle transfers of arbitrary amounts of data, up
to a maximum of 255 bytes, between the CPU and microcontroller. A
length parameter of zero transfers no data. Attenpts to transfer excess data
results in an error.
Opcode Command Argument Returned Function
0x40 Read EEPROM length offset ack + <data> This command reads arbitrary amounts of data, up
to a maximum of 255 bytes, from the EEPROM. A
length parameter of 0 (zero) transfers no data.
Attempts to transfer excess data returns an error.
0x41 Write EEPROM length offset <data> ack This command writes an area of EEPROM. If the
area to be written includes part of the factory area,
and this is write-protected, then the status byte will
indicate the error condition.
0x42 Write to Status
Display length offset <data> ack This command writes a string to the status display.
The offset argument is used to determine the
position of the string on the LCD display, which is
made up of two lines, each of 16 characters. The
top line of the display is addressed with offsets 0x0
to 0xE, the bottom line with offsets 0x40 to 0x4E
0x43 Define Special
Character length offset <data> ack This command writes a string to the
microcontroller which is interpreted as a definition
of a special character to be displayed on the status
screen. 8 bytes of data are required per character,
and the following offsets may be used to define
special status symbols:
0 WAN1 active
1 WAN2 active
2 LAN1 active
3 LAN2 active
4 PCMCIA active
5 DC good
6 Backslash (used for disk spinner)
Table 12-4 Block Transfer Commands
S3GX_TRMBook Page 15 Friday, September 19, 1997 11:39 am