USB-ISS Multifunction USB Communications Module
Technical Specification
Overview
The USB-ISS Multifunction USB Communications Module provides acomplete interface between your PC and the I2C bus, SPI bus, a Serial portand general purpose Analogue Input or Digital I/O. The module is poweredfrom the USB. Operating voltage is selectable between 3.3v and 5v. and can supply up to80mA at 5v for external circuitry from astandard 100mA USB port.
Windows 10 Compatibility If you upgrade from Windows 7 or Windows 8.1 to Windows 10, some features of the installed drivers and software may not work correctly. Download the latest drivers, software, firmware, and diagnostics for your HP products from the official HP Support website.
| USB-I2C | USB-ISS |
| USB Powered | |
| Support I2C at 100khz | |
| Support I2C at 20khz-1000khz | Fixed 20,50,100,400 &1000khz |
| I2C + I/O | |
| SPI Mode | 24khz to 3Mhz |
| Serial Mode | 300baud to 115200baud |
| I2C Direct | Used to build custom I2C sequences |
| Bootloader for user updates | Uses Microchip Bootloader |
| Supply power to external Circuit | Up to 80mA for USB-ISS |
| 5v operation | |
| 3.3v operation | |
| Mounting holes on PCB |
Documentation
This documentation is divided up into 6 pages.
1. This page describes the connections to the USB-ISS, the USBdriver installation and setting of the USB-ISS operating modes.
Five further pages describe the operational commands and the Boot-Loader.
2. I2C Operation, describes all the I2Ccommands available
3. SPI Operation, describes the format forSPI communication
4.Serial Operation, describes how to sendand receive serial data.
5. I/O Operation, describes how to setpins high/low and read digital or analogue inputs.
6. Boot Loader, describes how to update thefirmware in the USB-ISS.
First Step - Get The Drivers
Before connecting the USB-ISS module, you should downloadthe driver and unzip it to a temporary folder. Now connect the USB-ISSmodule and navigate windows to the temporary folder and install the driver.The USB-ISS will now appear as a COM port.
Which COM port?
After installing the drivers, and plugging in the USB-ISS module to a spare USBport, you will want to know which COM port it has been assigned to. This willvary from system to system depending on how many COM ports you currently haveinstalled. To find out where it is, right click on your 'My Computer'desktop icon and select 'Properties->Hardware->Device Manager'. Now scroll down andopen the 'Ports (COM & LPT)' tab. You should see the USB serialport listed - COM5 in the example below. If you want to change the COM portnumber - just right click on it, select properties, select advanced and selectthe COM port number from the available list. The COM port default will probably be set up for 9600 baud, 8 data bits, no parity and one stop bits, but what ever it is just ignore it. These settings are not actually used because we have a full 12Mbits USB connection right into the heart of the processor.
Connections
The diagram below shows the connections for the various modes.
| Power Link - Remove for 3.3v operation. | |||||||||||||||||||||||||||||||||||
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| Bootloader Link - Fit link for Bootloader mode |
3.3v or 5v
Add the link for 5v, remove it for 3.3v
The processor on the USB-ISS is equally happy running from 3.3v or from 5v.With the LEDs it takes up to 20mA so when 5v is selected by linking the powerselect pins, the USB-ISS module can supply up to 80mA to externaldevices. When the link is removed a 3.3v regulator supplies the power. Thisregulator is capable of 50mA, so when running at 3.3v up to 30mA is available toyour circuits. If your application requires more than this, or has its own supply, thenleave the 3.3v/5v pin unconnected. Do not apply your own voltage to this pin.
LEDs
The Green Led is a power indication and is on all the time the module isconnected to a powered USB port. The Red LED will flash whenever there is avalid I2C or SPI command received.
I/O pins
Each I/O pin, 1 to 4, may be individually selected to be Analogue Input or DigitalInput or Digital Output.
Inputs will not accept voltage higher than the supply, so whenoperating at 3.3v the inputs are NOT 5v tolerant.
Analogue inputs span from 0v to the supply for a range of 0-1023 (10-bit A/Dconversion).
SCL and SDA
These pins are the I2C bus connections. They should be connected directly to theSCL and SDA pins on your I2C device. The USB-ISS module is always a bus master,and is fitted with 4.7k pull-up resistors on the PCB. These resistors areautomatically disconnected in other modes.
SDI, SCK, SDO and CE
SDI is the SPI input to the USB-ISS, connect it to SDO on your device.
SDO is the SPI output from the USB-ISS, connect it to SDI on your device.
SCK is the SPI clock output from the USB-ISS, connect it to SCK on your device.
CE is the active low chip enable signal, connect it to CE on your device.
Tx and Rx
These are logic level signals, not RS232. Do not connectthis to an RS232 port without using a suitable RS232 logic level inverter chip.
0v Ground
The 0v Ground pin must be connected to the 0v (Ground) on your device.
Setup Commands
The USB-ISS command (0x5A) is used for internal operations. The arethree sub-commands:
| Command | SubCommand | Description |
| USB-ISS (0x5A) | ISS_VERSION (0x01) | Returns 3 bytes, the module ID (7), firmware version (currently 2), and the current operating mode. |
| USB-ISS (0x5A) | ISS_MODE (0x02) | Sets operating mode, I2C/SPI/Serial etc. See next section for details |
| USB-ISS (0x5A) | GET_SER_NUM (0x03) | Returns the modules unique 8 byte USB serial number. |
ISS-VERSION will return three bytes. The first is theModule ID, this will always be 7. The second byte is the firmware revisionnumber. The third byte is the current operating mode, ISS_MODE. This isinitialized to 0x40 (I2C-S_100KHZ) on power up.
Example:
Send 0x5A, 0x01.
Receive 0x07, 0x02, 0x40.
GET_SER_NUM will return the modules unique 8 byte USB serialnumber.
Example:
Send 0x5A, 0x03.
Receive 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x31. (that's'00000001')
The received serial number will always be ASCII digits in the range'0' to '9' ( 0x30 to 0x39 ).
ISS_MODE sets the operating mode. This sets up the modules I/O pins andhardware for the required mode. There are 4 operating modes (I2C, SPI, Serialand I/O) some which can be combined. I2C mode is further broken down into thevarious fixed frequencies and the use of software (bit bashed) or hardware I2Cports. The full list is:
| Operating Mode | Value |
| IO_MODE | 0x00 |
| IO_CHANGE | 0x10 |
| I2C_S_20KHZ | 0x20 |
| I2C_S_50KHZ | 0x30 |
| I2C_S_100KHZ | 0x40 |
| I2C_S_400KHZ | 0x50 |
| I2C_H_100KHZ | 0x60 |
| I2C_H_400KHZ | 0x70 |
| I2C_H_1000KHZ | 0x80 |
| SPI_MODE | 0x90 |
| SERIAL | 0x01 |
I/O_CHANGE is not really an operating mode. It's used to changethe I/O mode between Analogue Input, Digital Input and digital Output withoutchanging Serial or I2C settings.
The I2C modes will have I/O on the I/O1 and I/O2 pins.
Serial mode will have I/O on the I/O3 and I/O4 pins.
I2C and Serial can be combined, for example I2C_S_100KHZ (0x40) + SERIAL (0x01)= 0x41.
SPI requires all four I/O pins so there are no other options for this mode.
| IO_MODE | ||
I/O mode requires one further IO_TYPE byte to set the I/O type for each pin. | ||
| The IO_TYPE byte is made up from 4 pairs of bits, 1 pair for each I/O pin - 4B,4A, 3B,3A, 2B,2A, 1B,1A | ||
where each pair is: | xB xA | |
| 0 0 | Output Low | |
| 0 1 | Output High | |
| 1 0 | Digital Input | |
| 1 1 | Analogue Input | |
For example 0x01 (binary 00000001) would set I/O1 to output highand I/O's 2-4 to output low.
0xB4 (binary 10110100) would set I/O4 to digital input, I/O3 to analogue input,I/O2 to output high and I/O1 to output low.
The four byte command to set I/O mode is:
| ISS_CMD | ISS_MODE | IO_MODE | IO_TYPE (see example above) |
| 0x5A | 0x02 | 0x00 | 0xB4 |
I/O mode may be combined with SERIAL mode.
When combined with SERIAL, I/O1 is the Rx pin and I/O2 is the Tx pin. Only I/O3and I/O are available as I/O pins.
This is a 6 byte setup command.
| ISS_CMD | ISS_MODE | IO_MODE+SERIAL | Baud rate divisor (high byte) | Baud rate divisor (low byte) | IO_TYPE (see example above) |
| 0x5A | 0x02 | 0x01 | 0x00 | 0x9B | 0xB0 |
In all mode setting commands, two bytes are returned. See ResponseBytes below.
The formula for calculating the baud rate is:
x = (48000000/(16+baud rate))-1
For example if the required baud rate is 19200
(48000000/(16*19200))-1 = 155.25 so we will use 155.
155 is 0x009B so we set the high byte to 0x00 and the low byte to 0x9B.
Here are some standard baud rates:
| Baud Rate | Divisor | High Byte | Low Byte |
| 300 | 9999 | 0x27 | 0x0F |
| 1200 | 2499 | 0x09 | 0xC3 |
| 2400 | 1249 | 0x04 | 0xE1 |
| 9600 | 311 | 0x01 | 0x37 |
| 19.2k | 155 | 0x00 | 0x9B |
| 38.4k | 77 | 0x00 | 0x4D |
| 57.6k | 51 | 0x00 | 0x33 |
| 115.2k | 25 | 0x00 | 0x19 |
The serial mode is compatible with both 1 and 2 stop bit formatsbecause is transmits 2 stop bits and only needs to receive 1. There is noparity.
IO_CHANGE
Not really an operating mode. It's used to changethe I/O mode between Analogue Input, Digital Input and digital Output withoutchanging Serial or I2C settings. It only needs to be used when you are usingSerial or I2C modes and you want to change the I/O pins. The format is:
| ISS_CMD | ISS_MODE | IO_MODE | IO_TYPE (see example above) |
| 0x5A | 0x02 | 0x10 | 0xB4 |
In all mode setting commands, two bytes are returned. See ResponseBytes below.
I2C Modes
There are 7 I2C commands as detailed above. They differ only in the SCLfrequency and whether they use a software bit bashed driver or the I2C hardwarein the PIC chip.
The I2C command on its own will have I/O on pins I/O1 and I/O2. This is a 4 bytesetup command.
| ISS_CMD | ISS_MODE | I2C_MODE | IO_TYPE (see I/O mode above) |
| 0x5A | 0x02 | 0x60 | 0x04 |
This example will initialize I2C to 100khz using the hardwareI2C peripheral in the PIC chip.
The I2C commands may be combined with SERIAL mode.
When combined with SERIAL, I/O1 is the Rx pin and I/O2 is the Tx pin. This is a5 byte setup command.
| ISS_CMD | ISS_MODE | I2C_MODE+SERIAL | Baud rate divisor (high byte) | Baud rate divisor (low byte) |
| 0x5A | 0x02 | 0x71 | 0x00 | 0x9B |
The formula for calculating the baud rate is the same as for I/O+Serialabove.
In all mode setting commands two bytes are returned. See ResponseBytes below.
SPI Mode
This mode requires all four I/O pins, so cannot be combined with serial, I2C orI/O. Refer to the connection diagram above for pin-outs. SPI mode is capable ofoperating in all four possible clock phases. SPI_MODE command (0x90) maycombined with the phase selection bits.
| SPI_MODE | Phase |
| 0x90 | Tx on transition from active to Idle clock, Idle state for clock is low level |
| 0x91 | Tx on transition from active to Idle clock, Idle state for clock is high level |
| 0x92 | Tx on transition from Idle to active clock, Idle state for clock is low level |
| 0x93 | Tx on transition from Idle to active clock, Idle state for clock is high level |
0x90 is the standard mode, use this with SPI SRAM, EEPROM's etc.
Setting SPI mode is a 4 byte command:
| ISS_CMD | ISS_MODE | SPI_MODE | SCK divisor |
| 0x5A | 0x02 | 0x90 | 0x01 |
The SCK divisor sets the SPI clock speed. The formula is:
Divisor = (6000000/SCK)-1
For a 3Mhz SCK, divisor = (6000000/3000000)-1 = 1
For 500khz SCK, divisor = (6000000/500000)-1 = 11
The maximum divisor of 255 gives the slowest SCK of just 23.44khz.
A minimum of 0x01 should be set for the divisor, if you set 0x00 it will be thesame as 0x01.
In all mode setting commands, two bytes are returned. See ResponseBytes below.
Response Bytes
The response to the mode setting frames is always two bytes.
The first byte is ACKnowledge (0xFF) or NotACKnowledge (0x00).
If you get an ACK then the second byte will be just 0x00.
If you get a NACK then the second byte will be the reason, as follows:
0x05 Unknown Command
0x06 Internal Error 1 }
0x07 Internal Error 2 } you should never see these
Under normal circumstances the response will be 0xFF, 0x00
| Further Technical Pages | ||||
| I2C | SPI | Serial | I/O | Boot-Loader |
Testing the USB-ISS
We have a small test program which will let you try out the different operatingmodes of the USB-ISS module. It is written in Visual C# 2010 version.
| Left Image show test of Hardware I2C at 400khz with I/O. It is writing and reading a four byte (32 bit) integer. The I/O has been set to analogue and the measured values are displayed. Right |
You can download just the executable filesor the full source code.
Dimensions
-->This article describes how you can control when Windows Update distributes your driver.
When submitting a driver to Windows Update, the Driver Delivery Options section presents two radio buttons: Automatic and Manual
Under the Automatic option there are two checkboxes: Automatically delivered during Windows Upgrades and Automatically delivered to all applicable systems. Automatic is the default setting for all new shipping labels.
When the first checkbox is selected, the driver is classified as a Dynamic Update (a term that applies to upgrade scenarios). Windows automatically preloads drivers in this category when upgrading the OS.
When the second checkbox is selected, the driver is downloaded and installed automatically on all applicable systems once it is released. All Automatic drivers must first have been evaluated by Microsoft through Driver Flighting.
For more info about the Manual option, see Publish a driver to Windows Update.
User plugs in a device
When a device is connected to a Windows system:
Plug and Play (PnP) looks for a compatible driver already available on the computer. If one exists, Windows installs it on the device. Then, during the next daily scan of Windows Update, Windows searches for a more up-to-date version of the driver. This can take up to 24 hours from when the device is plugged in.
If there is no compatible driver on the computer, Windows searches Windows Update for the highest-ranking Automatic driver.
When searching Windows Update:
In Windows 10, version 1909 and earlier, if no Automatic driver is available for the device, Windows proceeds to the highest-ranking Manual driver.
Starting in Windows 10, version 2004, Windows does not search for a Manual driver when an Automatic driver is not available. For info on how to access Manual drivers, see the Windows Update section of this page.
Device Manager
In Device Manager, when a user selects Update driver:
- In Windows 10, version 1909 and earlier, Windows installs the highest-ranking driver from Windows Update, regardless of whether it is classified as Automatic or Manual.
- Starting in Windows 10 version 2004, Windows only searches the local computer.
When it fails to find a driver, Device Manager shows a button labeled Search for updated drivers on Windows Update, which opens the Settings app to the Windows Update page. To find this button, right-click a device and select Properties. On the Driver tab, select Update Driver and then Search automatically for drivers.
- Starting in Windows 10, version 2004, click Search for updated drivers on Windows Update and then select View optional updates->Driver updates to download Manual drivers.
- In earlier versions of Windows, Device Manager downloads Manual drivers on its own.
Windows Update
During a Windows Update scan (scheduled or user-initiated):
In Windows 10, version 1909 and earlier, Windows Update automatically distributes Manual drivers in either of the following scenarios:
- A device has no applicable drivers available in the Driver Store (raising a 'driver not found' error), and there is no applicable Automatic driver
- A device has only a generic driver in the Driver Store, which provides only basic device functionality, and there is no applicable Automatic driver
Starting in Windows 10, version 2004, Windows Update distributes only Automatic drivers for a system's devices. When Manual drivers are available for devices on the computer, the Windows Update page in the Settings app displays View optional updates .
Summary
Devantech Driver Download For Windows 10
The following table summarizes the information above. Windows Update is abbreviated WU.
Devantech Driver Download For Windows
| Driver delivery options | OS upgrades | Connecting new device | Device Manager | WU scan | WU Optional updates page |
|---|---|---|---|---|---|
| Automatic (both checkboxes) | Yes | Only if the local driver is generic or missing | Only in Windows 10, version 1909 and earlier | Yes | No |
| Automatic (to all applicable systems) | No | Only if the local driver is generic or missing | Only in Windows 10, version 1909 and earlier | Yes | No |
| Automatic (during Windows Upgrades) | Yes | Only if the local driver is generic or missing | Only in Windows 10, version 1909 and earlier | Only if the local driver is generic or missing | No |
| Manual in Windows 10, version 1909 and earlier | No | Only if the local driver is generic or missing, and WU has no applicable Automatic driver | Yes | Only if the local driver is generic or missing, and WU has no applicable Automatic driver | N/A |
| Manual in Windows 10, version 2004 and later | No | No | No | No | Yes |