Video Test Generator User Guide 379
I2CR? I2C port Read
Class EDID and DDC control
Description Automatically reads data using a specified I2C protocol. This command reads data from
the DDC port (if equipped), EDID, enhanced DDC (E-DDC) data, and VESA DDC/CI
(DDC2Bi) data using the I2C bus. All numeric parameters are given in ASCII HEX.
Note: EDID-compatible receivers use EPROMs with single-byte or double-byte
addresses. The I2CR? query uses different parameters depending on the EPROM
type. To determine which EPROM type is used, try both syntaxes until you can read
data from the EPROM.
Query syntax
(EPROM with
single-byte
addresses)
I2CR? eprom i2c_address offset #_of_bytes
Query syntax
(EPROM with
double-byte
addresses)
I2CR? eprom1 i2c_address offset #_of_bytes
Query syntax
(DDC/CI protocol) I2CR? ddcci dst_address #_of_bytes
Query syntax
(E-DDC protocol) I2CR? e_ddc ddc_pointer_addr segment# i2c_address offset #_of_bytes
i2c_address (hex)
i2c bus address (A0, A1,...)
offset (hex)
address offset (in bytes)
#_of_bytes (hex)
number of bytes
dst_address (hex)
destination address
ddc_pointer_addr (hex)
segment pointer address
segment# (hex)
segment pointer number