ADS1100: Configuration Register values not updating

Good afternoon,

We are trying to use an ADS1100 and are having trouble with the configuration register, it does not seem to update based upon our commands.  I was not able to find any documentation regarding the number of the configuration register, so I've just been doing simple 'write' commands across the I2C.  I have been successfully reading from register 0x00.

Here is the behavior, regardless of what byte we send, the configuration register does not change.

upon start-up we perform a read, the 3rd byte is '128'

we send 0x00 and then perform a read, the 3rd byte is '128' as expected, but that doesn't tell me I actually did anything

we send 0x04 and then perform a read, the 3rd byte is '128'

we send 0x08 and then perform a read, the 3rd byte is '128'

we send 0x0C and then perform a read, the 3rd byte is '128'

Below is our console output, followed by our test script.

Any assistance is appreciated

Thanks

Read register: 3 95 128
Trying to set register to 0
Read register: 3 95 128
Trying to set register to 4
Read register: 13 123 128
Trying to set register to 8
Read register: 26 232 128
Trying to set register to C
Read register: 53 218 128

from smbus2 import SMBus
import time

# Get I2C bus
bus = SMBus(2)

# ADS1100 address, 0x48(72)
# Select configuration register
# 0x0C(12) Continuous conversion mode, 8 SPS, 1 PGA

time.sleep(0.5)

data = bus.read_i2c_block_data(0x48, 0x00, 3)
print("Read register: %d %d %d" %(data[0], data[1], data[2]))

print("Trying to set register to 0")
bus.write_byte(0x48, 0x00)

time.sleep(0.5)

data = bus.read_i2c_block_data(0x48, 0x00, 3)
print("Read register: %d %d %d" %(data[0], data[1], data[2]))

time.sleep(0.5)

print("Trying to set register to 4")
bus.write_byte(0x48, 0x04)

time.sleep(0.5)

data = bus.read_i2c_block_data(0x48, 0x00, 3)
print("Read register: %d %d %d" %(data[0], data[1], data[2]))

time.sleep(0.5)

print("Trying to set register to 8")
bus.write_byte(0x48, 0x08)

time.sleep(0.5)

data = bus.read_i2c_block_data(0x48, 0x00, 3)
print("Read register: %d %d %d" %(data[0], data[1], data[2]))

time.sleep(0.5)

print("Trying to set register to C")
bus.write_byte(0x48, 0x0C)

time.sleep(0.5)

data = bus.read_i2c_block_data(0x48, 0x00, 3)
print("Read register: %d %d %d" %(data[0], data[1], data[2]))