Part Number:UCD9090
Hi,
I have a working configuration for a UCD9090 device. To simplify production / in-field upgrades I am now trying to move the configuration to a Microcontroller.
With this I now see the device configuration failing .... when configuring a GPIO the read-back from the device returns a different value than what the generated script specifies.
This is the section of the script that fails (highlighted in red)
// Write GPIO_CONFIG_3 [MFR 43] Enable: False; Out_Enable: False; Out_Value: False; Status: False
WriteByte 0x68 0xFA 0x03 0xB0
ReadByte 0x68 0xFA 0x03
WriteByte 0x68 0xFB 0x00 0xAC
ReadByte 0x68 0xFB 0x00
// Write GPIO_CONFIG_4 [MFR 43] Enable: False; Out_Enable: False; Out_Value: False; Status: True
WriteByte 0x68 0xFA 0x04 0xA5
ReadByte 0x68 0xFA 0x04
WriteByte 0x68 0xFB 0x08 0x94
ReadByte 0x68 0xFB 0x00
It appears that the device returns 0x08 instead of 0x00, so exactly what was written (I have monitored this with an Logic Analyzer).
I am a bit puzzled about the value being written in the first place - according to the "UCD90xxx Sequencer and Health Contoller PMBus Command Reference (Rev. F)" (section 10.43) the status bit is a read only bit - why does Fusion Designer attempt to write it in the first place.
The description is also not very clear - what exactly does the bit signify?
In Fusion Designer GPIO 4 is configured as active high output (Enable Pin for Rail #1). At the time when I was re-configuring the device the output should have been low, so if anything I would have expected a '0', not a '1' as actually found.
For your reference the Fusion Designer project file and generated script can be found in attached zip file.(Please visit the site to view this file)
The version of Fusion Digital Power Designer used is 2.0.179
Many thanks for your inputs!
Rene