From hardware part MiDi and DMX 512 are similar.
DMX uses a differece signal transmission like the RS485 Protocol.
So you can use RS485 driver like the SN75176.
DMX is in the opposite to MiDi not galvanic isolated.
It's better to do this, but it's not a must of specification.
Data Speed is 250kBit/s, 8 Data Bits and 2 Stop Bits!
The Frame Start is pointed by an Frame Error, followed by a Start Byte that includes most 0x00 ( = Dimmer ). Then follow 512 Bytes of DMX Channel Information.
Because there are 8 Bytes you can differ 256 different values.
The Channel finding, in receiver, can be done, by counting the Bytes after the Start Byte.
The data transfer is only unidirectional. There are no "Back" channels included.
Maximum 32 Units can be connected to 1 Master. A Unit can use 1 or more channels, up to 512 of course. Further bus drivers can be included to increase the range or to connect more unit's to the bus. The maximum Range is about 1km theoreticly. In practic use it should be under 500m.
The used cable is very importent. I'll use an CAT5 Network Patch Cable - Because it's the cheapest solution - You need much of them!
The Bus must be terminated with an 120R Resistor at the begin and the end of the bus. That can be done by a XLR Male Connector with integrated Resistor in Receiver and a fixed Resistor into the Master.
When you put 2 Line Drivers onto the Evaluation Bord you can use it for both - MiDi and DMX. The rest is software