collapseos/blk/420

SD Card subsystem

Load range: B423-B436

This subsystem is designed for a ad-hoc adapter card that acts
as a SPI relay between the z80 bus and the SD card. It requires
a driver providing the SPI Relay protocol. You need to define
SDC_DEVID to specify which ID will be supplied to (spie).

Through that layer, this driver implements the SDC protocol
allowing it to provide BLK@ and BLK!.
Move SD Card subsystem outside of RC2014 recipe and add protocols Although the SPI Relay driver is RC2014-specific, the SD Card driver is generic enough to be a subsystem. That's the second subsystem we add and this warrants, I think, the formalization of a new concept: protocols. 2020-08-17 04:30:33 +10:00			`SD Card subsystem`

			`Load range: B423-B436`

			`This subsystem is designed for a ad-hoc adapter card that acts`
			`as a SPI relay between the z80 bus and the SD card. It requires`
Make the SPI Relay protocol support multiple devices Working on programming AVR chips exposes a glaring omission in my first design of the SPI Relay: not allowing multiple devices make this task hard. I constantly have to unplug my SD card before, plug the AVR chip holder, then play a bit, then unplug the AVR holder, then replug the SD card... My prototype for a SPI relay design is built, but I haven't tested it yet. I need to adapt the code first, which is what I do here. When the prototype is tested, I'll update the SDC recipe with a new schema. 2020-09-17 23:36:16 +10:00			`a driver providing the SPI Relay protocol. You need to define`
			`SDC_DEVID to specify which ID will be supplied to (spie).`
Move SD Card subsystem outside of RC2014 recipe and add protocols Although the SPI Relay driver is RC2014-specific, the SD Card driver is generic enough to be a subsystem. That's the second subsystem we add and this warrants, I think, the formalization of a new concept: protocols. 2020-08-17 04:30:33 +10:00
			`Through that layer, this driver implements the SDC protocol`
			`allowing it to provide BLK@ and BLK!.`