Introduction
This is the documentation of the low level feature report protocol of the Arcaze USB-Interface.
Please do only use this low level protocol, if you know why you’re doing it. When coding on a Windows platform, using the supplied Arcaze DLL is generally preferable, as it simplifies and harmonizes usage and also covers changes in the low level protocol. Changes are not overly common, but be aware that the feature report commands are subject to change (as opposed to the DLL functions).
The main reason to use this low level feature report protocol, would be platform independence, as currently there is no Arcaze DLL implementation for other platforms than MS Windows.
First experiences with the feature report protocol can be collected on the “Low Level Feature Reports” tab of the Arcaze DLL Demo:
Implementation
There are various libraries simplifiying the transfer of USB feature reports on different operating systems. Some of them will be shown here. Feel free to contribute your favorite API.
HIDAPI
The HIDAPI library is available for Windows, Linux, and Mac OS X based platforms. Documentation and download are available here: http://www.signal11.us/oss/hidapi/
Basic communication can be as simple as this (minus all error checking):
// Establish USB connection
handle = hid_open(0x1690, 0xfe13, NULL);
// Prepare out report data ("Read Ports" command)
buf[0] = 0x00;
buf[1] = 0x08;
// Send out report
res = hid_send_feature_report(handle, buf, 65);
// Receive in report
res = hid_get_feature_report(handle, buf, sizeof(buf));
Command Reference
All command IDs are noted in decimal.
Multiple Byte values are transmitted with lowest byte first (“Litte Endian” / “LSB first”).
Memory Access Commands
These commands are used to write a new configuration to the Arcaze USB-Interface.
| Command | ID | Description |
|---|---|---|
| ReadRam | 2 | Read TransferRAM contents from Arcaze |
| WriteToRam | 3 | Write TransferRAM contents in Arcaze |
| CopyFlashToRam | 4 | Copy Flash contents to TransferRAM |
| ClearFlash | 5 | Erase a flash sector |
| ProgRamToFlash | 6 | Program Flash sector from TransferRAM |
| ClearRam | 7 | Clear TransferRAM contents |
System Commands
| Command | ID | Description |
|---|---|---|
| ValidateConfig | 12 | Validate a configuration after copying it to flash. |
| InvalidateConfig | 13 | Invalidate a configuration. Arcaze will not use it anymore. |
| ReadStatus | 17 | Reads status of configuration (valid / invalid) |
| ReadConfigNumber | 18 | Reads ID of the currently active configuration |
| StartMacros | 21 | Start execution of all macros in configuration |
| StopMacros | 22 | Stop execution of all macros in configuration |
| SetConfig | 28 | Activates a specific configuration |
| Reset | 252 | Soft-Resets the whole Arcaze USB-Interface |
| ReadBootSerialNumber | 253 | Reads base serial number of the USB-Interface |
| Enumerate | 254 | Resets the USB bus only / Re-Enumerates |
| InvalidateFirmware | 255 | Invalidates the firmware. Firmware update will be mandatory after this command! |
Onboard Port Commands
| Command | ID | Description |
|---|---|---|
| ReadPorts | 8 | |
| ReadADC | 27 | |
| SetPinDirection | 29 | |
| SetPin | 30 | |
| SetPortDirection | 31 | |
| SetPort | 32 | |
| ReadQuadratureEncoders | 44 | |
| ReadPortsWithHistory | 45 |
Display Driver Commands
| Command | ID | Description |
|---|---|---|
| CmdIdMax7219DisplayInit | 33 | |
| CmdIdMax7219WriteReg | 34 | |
| CmdIdMax7219ReadReg | 35 | |
| CmdIdMax7219WriteDigits | 36 |
LED Driver 2 Commands
| Command | ID | Description |
|---|---|---|
| CmdIdTlc5926Init | 37 | |
| CmdIdTlc5926WriteLeds | 38 | |
| CmdIdTlc5926StrobeEnable | 39 |
LED Driver 3 Commands
| Command | ID | Description |
|---|---|---|
| CmdIdTlc5943Init | 40 | |
| CmdIdTlc5943WriteLeds1Bit | 41 | |
| CmdIdTlc5943WriteLeds8Bit | 42 | |
| CmdIdTlc5943Strobe | 43 |
Command Descriptions
Feature Report Length & Report ID
All in and out feature reports are 64 bytes long, without any exception. Do not send a different number of bytes.
But be aware of the Feature Report ID. On MS Windows based systems, this ID normally is simply prefixed to the actual feature report data. Therefore the feature report data actually sent/received is one byte longer than described in the command descriptions below, which don’t include it, as it’s not part of the protocol.
Currently we are not using the USB Feature Report IDs, therefore this byte is always 0x00.
To conclude:
- If your USB stack requires the Report ID to be included with the report data, always send 65 bytes. First byte is 0x00 and Command starts at second byte.
- Otherwise send and receive 64 bytes.
Status Return Values
Many commands return a status value. This can be one of the following values:
| Name | Value |
|---|---|
| STATUS_SUCCESS | 0 |
| STATUS_WRITE_OUTSIDE_RAM | 1 |
| STATUS_READ_OUTSIDE_RAM | 2 |
| STATUS_WRONG_SECTOR | 3 |
| STATUS_FLASH_FAILURE | 4 |
| STATUS_COMMAND_NOT_IMPLEMENTED | 5 |
| STATUS_WRONG_HASH | 6 |
| STATUS_INVALID_PORT_NUMBER | 7 |
Memory Access Commands
READ_RAM (2)
Read Data from the TransferRAM. This is mainly used together with CMD_COPY_FLASH_TO_RAM.
The Out Feature Report sets the base address of the data to be read. With every In Feature Report the base address is incremented by the number of received bytes. Therefore it’s also possible to do “burst reads” with one Out Report, setting the start address and multiple In Reports to read the data continuously.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 2 | 1 | CMD_READ_RAM |
| 1 | Address | 2 | Start address for read. This is the relative address inside the TransferRAM, first byte has address 0. | |
| 3…63 | Not used | Not used |
No length is submitted. The In report is always completely filled until the end of the RAM block is reached or the internal number of valid bytes is reached.
In Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 2 | 1 | CMD_READ_TRANSFER_RAM |
| 1 | Status | 1 | Status Return Value | |
| 2 | Address | 2 | Base address of Data | |
| 4 | Length | 1 | Number of valid bytes in this report | |
| 5…63 | Payload | 58 | Payload data |
In reports can be polled until end of RAM block is reached (address 0x0fff). Continued reads supply all zeros.
Additionally note that the firmware also respects the number of valid bytes in RAM. So, if by a previous command only the first 256 bytes have been written, it’s not possible to read above address 0x00ff. When reading above, the data is all zero.
WRITE_RAM (3)
Write Data to TransferRAM.
This Out Feature Report can write a maximum of 58 bytes into TransferRAM. Every Out Feature Report sets the destination address, therefore there is no burst mode here.
Important: Note that you have to issue a CMD_CLEAR_FLASH_RAM before being able to write to Flash RAM for security reasons!
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 3 | 1 | CMD_WRITE_RAM |
| 1 | Address | 2 | Start address for write. This is the relative address inside the Flash RAM, first byte has address 0. | |
| 3 | Length | 1 | Number of bytes to write in this report. | |
| 4…61 | Payload | 58 | Payload (maximum size is 58 bytes!) |
It’s possible to write to any address between 0x0000 and 0x0fff. All other writes are ignored and an RETVAL_WRITE_OUTSIDE_RAM error is issued.
COPY_FLASH_TO_RAM (4)
Copies addressed data from a flash sector to the TransferRAM.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 4 | 1 | CMD_COPY_FLASH_TO_RAM |
| 1 | SectorID | 1 | Sector ID to be read. Refer to sector table. | |
| 2…63 | Not used | Not used |
CLEAR_FLASH (5)
Erase a flash sector.
Access restrictions apply. If a user is not entitled to erase this sector it is denied. Refer to flash sector table to see which sectors allow erasing.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 5 | 1 | CMD_CLEAR_FLASH |
| 1 | SectorID | 1 | Sector ID to be erased. Refer to sector table. | |
| 2…63 | Not used | Not used |
COPY_RAM_TO_FLASH (6)
Programs Transfer RAM contents into Flash Memory.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 0d6 | 1 | CMD_COPY_RAM_TO_FLASH |
| 1 | SectorID | 1 | SectorID | |
| 3…63 | Not used |
In Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 6 | 1 | CMD_COPY_RAM_TO_FLASH |
| 1 | Return Value | 1 | Return Value refer to table of status return values |
CLEAR_RAM (7)
Clears the complete TransferRAM (4kBytes total) by overwriting all bytes with 0xFF.
Important: Note that you have to issue a CMD_CLEAR_RAM before being allowed to write to TransferRAM for security reasons! The number of valid data bytes in TransferRAM is set to 0x1000 by this command, so all data bytes can be read and overwritten afterwards.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 7 | 1 | CMD_CLEAR_RAM |
| 1…63 | Not used |
System Commands
TBD
Onboard Port Commands
READ_PORTS (8)
Reads states of internal digital ports.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 8 | 1 | CMD_ID_READ_PORTS |
| 1…63 | Not used |
In Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 8 | 1 | CMD_ID_READ_PORTS |
| 1 | Status | 0 | 1 | STATUS_SUCCESS |
| 2 | Reserved | x | 1 | Reserved (was LastChanged, but currently not implemented) |
| 3 | Port A1 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 4 | Port A2 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 5 | Port A3 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 6 | Port A4 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 7 | Port A5 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 8 | Port A6 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 9 | Port A7 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 10 | Port A8 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 11 | Port A9 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 12 | Port A10 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 13 | Port A11 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 14 | Port A12 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 15 | Port A13 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 16 | Port A14 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 17 | Port A15 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 18 | Port A16 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 19 | Port A17 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 20 | Port A18 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 21 | Port A19 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 22 | Port A20 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 23 | Port B1 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 24 | Port B2 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 25 | Port B3 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 26 | Port B4 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 27 | Port B5 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 28 | Port B6 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 29 | Port B7 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 30 | Port B8 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 31 | Port B9 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 32 | Port B10 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 33 | Port B11 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 34 | Port B12 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 35 | Port B13 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 36 | Port B14 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 37 | Port B15 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 38 | Port B16 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 39 | Port B17 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 40 | Port B18 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 41 | Port B19 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 42 | Port B20 value | 0 or 1 | 1 | Actually only Bit 0 is used. Bits 1…7 are always 1 |
| 43…63 | not used | 0 | not used |
CMD_READ_ADC (27)
Reads ADC values of the 6 internal ADCs. Item size is 16 bits, but in Arcaze USB-Interface V3 only 10 bits are used. In Arcaze USB-Interface V4, 12 bits are used.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 27 | 1 | CMD_READ_ADC |
| 1…63 | Not used |
In Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 27 | 1 | CMD_READ_ADC |
| 1 | Status | 1 | ||
| 2 | ADC port 0 (AIN 1) value (LSB first) | 2 | ||
| 4 | ADC port 1 (AIN 2) value (LSB first) | 2 | ||
| 6 | ADC port 2 (AIN 3) value (LSB first) | 2 | ||
| 8 | ADC port 3 (AIN 4) value (LSB first) | 2 | ||
| 10 | ADC port 4 (AIN 5) value (LSB first) | 2 | ||
| 12 | ADC port 5 (AIN 6) value (LSB first) | 2 | ||
| 14…63 | not used |
SET_PIN_DIRECTION (29)
Sets I/O direction of a single onboard I/O pin.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 29 | 1 | CMD_SET_PIN_DIRECTION |
| 1 | NumPin | 0…39 | 1 | Number of onboard pin. 0…19=Port A, 20…39=Port B |
| 2 | Direction | 0 or 1 | 1 | 0=Input / 1=Output |
| 3…63 | not used | Not used |
SET_PIN (30)
Sets output level of a single onboard I/O pin.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 30 | 1 | CMD_SET_PIN |
| 1 | NumPin | 0…39 | 1 | Number of onboard pin. 0…19=Port A, 20…39=Port B |
| 2 | Value | 0 or 1 | 1 | 0=Low / 1=High |
| 3…63 | not used | Not used |
Physically 0 means low = 0V and 1 means high = 3.3V.
SET_PORT_DIRECTION (31)
Sets pin directions of all pins of a complete onboard I/O port (A or B). All 20 pins directions of the selected port are being overwritten.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 31 | 1 | CMD_SET_PORT_DIRECTION |
| 1 | NumPort | 0…1 | 1 | Number of onboard port 0=Port A, 1=Port B |
| 2 | Directions | 0…0xfffff | 4 | Bitmask: Bit 0 = pin 0 of selected port, bit 19= pin 19 of selected port. Bit value 0=input / bit value 1=output |
| 6…63 | not used | Not used |
SET_PORT (32)
Sets pin output values of all pins of a complete onboard I/O port (A or B). All 20 pins output values of the selected port are being overwritten.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 32 | 1 | CMD_SET_PORT |
| 1 | NumPort | 0…1 | 1 | Number of onboard port 0=Port A, 1=Port B |
| 2 | Values | 0…0x000fffff | 4 | Bitmask: Bit 0 = pin 0 of selected port, bit 19= pin 19 of selected port. Bit value 0=output low / bit value 1=output high |
| 6 | Action | 0=on 1=off 2= set | 1 | Selects how the port values are used: – On means that for each 1-bit in the port values mask a pin is being set to high and the others are not touched. – Off means that for each 1-bit in the port values mask a pin is being set to low and the others are not touched. – Set meand that all values are copied 1:1 to the ports. 1’s become output highs and 0’s become lows. No pins of the addressed port stay untouched. |
| 7…63 | not used | Not used |
READ_QUADRATURE_ENCODERS (44)
Read quadrature encoder values.
Quadrature encoders can be connected to each neighbouring pair of pins like A1/2, A3/4, … , B37/39, B39/40. So, total of 20 quadrature encoders can be connected. Each of these quadrature encoders is represented by a 16 bit signed integer value in this in report. It counts up when turned to one direction and counts down when turned to the other direction. It overflows from -32768 to 32767 and vice versa.
The values are not being reset at any time. To follow the rotation of a quadrature encoder, the value has to sampled twice and the difference between the values represents the number of pulses, the encoder has been rotated in the meantime.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 44 | 1 | CMD_READ_QUADRATURE_ENCODERS |
| 1…63 | not used | Not used |
In Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 0d | 1 | CMD_READ_QUADRATURE_ENCODERS |
| 1 | Status Return Value | 0 | 1 | SUCCESS |
| 2 | EncoderValues | -32768…32767 | 40 (2 bytes each) | Quadrature encoder counter values 0…19 |
READ_PORTS_WITH_HISTORY (45)
This is a more sophisticated version of the READ_PORTS command.
In addition to the current state of each onboard I/O pin, it also returns the number of changes each pin has experienced since the last READ_PORTS_WITH_HISTORY command. This can be helpful to find out, if any changes on a port have been missed since reading the port last time. Reasons may be insufficient polling frequency or bouncing of a switch for example.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 45 | 1 | READ_PORTS_WITH_HISTORY |
| 1…63 | not used | Not used |
In Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 45 | 1 | READ_PORTS_WITH_HISTORY |
| 1 | Status Return Value | 0 | 1 | SUCCESS |
| 2 | LastChanged | 0…40 | 0: no changes since last call 1…20: Last change was on Port A1…A20 21…40: Last change was on Port B1…B20 | |
| 3 | InputData | bitmask | 20 (1 byte per pin) | Bit 0: Current State of this Pin Bit 1..7: Number of changes on this pin since last call of READ_PORTS_WITH_HISTORY |
| 4…63 | not used |
The last changed value shows, which pin has changed last. In some situations it saves time to know this immediately.
Display Driver Commands
Display Driver Basics
The Display Driver modules are extension modules, connected to the extension port of the Arcaze-USB Interface.
Display Driver Types
Currently 2 different Display Driver Modules exist:
Display Driver 1
- This module contains only one display driver chip and therefore can drive 8 digits in total.
- The bus address can be set by a rotary switch to values 0 to 15.
- Theoretically up to 16 Display Driver 1 modules could be connected to an Arcaze USB-Interface.
- The Display Driver 1 is obsolete.
Display Driver 32
- This module contains 4 display driver chips and therefore can drive 32 digits in total.
- The bus address can be set by solder bridge SB101. When set to “1” or open, the bus addresses of the display driver chips are 0…3. When set to “2”, the bus addresses of the display driver chips are 4…7.
- 1 or 2 Display Driver 32 modules can be connected to an Arcaze USB-Interface.
Decode Mode
There are 2 different ways to display data sent to a display driver. The “Decode Mode” can be set up on a per-digit basis.
Decode Mode = 0 / Bitmapped Mode
If a digit is set up for deocde mode 0, the data is displayed as a bitmap exactly as it has been received. So each bit of a byte stands for one segment of a digit as shown here:
Decode Mode = 1 / Code B Decoding
If decode mode 1 is selected for a digit, a small character generator is used and only bits 0…3 of display data are interpreted and displayed as shown in the table below. Additionally bit 7 represents the DP point.
MAX7219_DISPLAY_INIT (33)
Initializes a display driver chip of a Display Driver Module connected to the extension port of the Arcaze USB-Interface.
A Display Driver 1 module contains only one display driver. Therefore, only one Init command is required per module. The Display Driver 32 module contains 4 display drivers, each with its own address. Therefore it’s necessary to send the init command 4 times, once to each address. This has not been combined into one command to allow for setting brightness or other settings different for each chip if desired.
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 33 | 1 | MAX7219_DISPLAY_INIT |
| 1 | Device Address | 0…7 | 1 | Bus address of the display driver chip. On a Display Driver 32 this can be 0..3 for the first module and 4…7 for the second module connected to the Arcaze USB-Interface. On a Display Driver 1 this can be 0…15, which is the address to be set by the rotary switch on each Display Driver 1 module. |
| 2 | Decode Mode | Bitmask | 1 | Each bit reflects one digit. If a bit is set to 0, display data is not decoded, but simply displayed as a bitmap for all segments of this digit. If a bit is set to 1, display data is decoded and displayed as Code B font, as shown in the Code B font table earlier. |
| 3 | Intensity | 0…15 | 1 | 0 = darkest, 15 = brightest |
| 4 | ScanLimit | 4…8 | 1 | Selects the number of digits to actually be updated from a display driver. This can generally be left at value 8. The only reason to alter this value, would be to achieve a higher frame update rate on a display smaller than 8 digits, as scanning becomes the faster, the less digits are to be updated. But this will only be relevant in very specific applications (like moving displays). |
| 5…63 | not used | not used |
The last changed value shows, which pin has changed last. In some situations it saves time to know this immediately.
MAX7219_WRITE_DIGITS (36)
Out Report
| Address | Content | Value | Length (Bytes) | Remarks |
|---|---|---|---|---|
| 0 | Command | 36 | 1 | MAX7219_WRITE_DIGITS |
| 1 | Device Address | 0…7 | 1 | Bus address of the display driver chip. On a Display Driver 32 this can be 0..3 for the first module and 4…7 for the second module connected to the Arcaze USB-Interface. On a Display Driver 1 this can be 0…15, which is the address to be set by the rotary switch on each Display Driver 1 module. |
| 2 | Digit 0 Data | 0x00…0xff | 1 | Display Data goes here. Can be bitmapped or Code B. Digit 0 is on the right side for displays attached to connector A and on the left side for displays attached to connector B |
| 3 | Digit 1 Data | 0x00…0xff | 1 | Display Data for digit 1 goes here. Can be bitmapped or Code B. |
| 4 | Digit 2 Data | 0x00…0xff | 1 | Display Data for digit 2 goes here. Can be bitmapped or Code B. |
| 5 | Digit 3 Data | 0x00…0xff | 1 | Display Data for digit 3 goes here. Can be bitmapped or Code B. |
| 6 | Digit 4 Data | 0x00…0xff | 1 | Display Data for digit 4 goes here. Can be bitmapped or Code B. |
| 7 | Digit 5 Data | 0x00…0xff | 1 | Display Data for digit 5 goes here. Can be bitmapped or Code B. |
| 8 | Digit 6 Data | 0x00…0xff | 1 | Display Data for digit 6 goes here. Can be bitmapped or Code B. |
| 9 | Digit 7 Data | 0x00…0xff | 1 | Display Data for digit 7 goes here. Can be bitmapped or Code B. Digit 7 is on the left side for displays attached to connector A and on the right side for displays attached to connector B |
| 10 | DigitsMask | 0x00…0xff | 1 | Bit 0 = Digit 0 … Bit 7 = Digit 7 |
| 11…63 | not used | not used |
Example Command
00 24 00 01 02 03 04 05 06 07 08 0f 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Results:
- Accesses display driver on bus address 0
- Writes 1 to digit 0
- Writes 2 to digit 1
- Writes 3 to digit 2
- Writes 4 to digit 3
- Does not change contents of digits 4 to 7, because their bits are set to 0 in the DigitsMask register!