Removing MIDI processing from IIC MIDI

MIOS programming (Assembler)
1

Hi.

I know that it isn’t ‘technically’ MIOS, but I have been building a MIDI<->RS-232 translator (for Sony Minidisc control) and I am using an IIC MIDI and an LTC module (I suppose you could call it “IIC RS-232”).

The IIC Midi code does quite a bit of processing to check that it is a valid Midi stream which I don’t want it to do. I have done a quick-and-dirty hack to prot.asm which forces all bytes to be sent as single byte MIDI (F8-FF) whereby I commented out andlx 0xf8 and xorlw 0xf8 in PROT_Tick_Rx_NewStatus!

I know that this isn’t perfect as it means that 2 bytes are sent over the I2C for each 1 byte of RS-232 but as I am working at 9600baud I wasn’t concerned about this.

Is there a more elegant way of achieving this? As it isn’t exactly easy to debug the IIC I didn’t want to change too much and I last used assembler on 6502’s in the late 80’s!

Phil

2

Perhaps the original suggestion might be easier to implement - use IIC_MIDI for midi, and use the core for RS232 ?

3

Hi Phil,

I’m planning to update the IIC_MIDI firmware soon to provide a “raw IO” mode.

So long it isn’t available, you could also use the MBHP_IIC_SPEAKJET firmware which already matches with your requirements.

Best Regards, Thorsten.