RS232 Projector Controller: Difference between revisions

Latest revision as of 09:34, 24 September 2025

RS232 Projector Controller


Ort	Hackcenter
Besitzstatus	Leihgabe
Kontakt	ente
Git-Repo	https://github.com/chaosdorf/projector-controller-iot

Controls the projector via its RS232 interface. Integrated into HomeAssistant via MQTT.

Location[edit | edit source]

Attached to truss next to projector in Hackcenter.

Technical Details (see git repo)[edit | edit source]

µC: ESP32-S3-WROOM with 8MB flash, SP3232EEN-L/TR RS232 transceiver

Programmable via UART, JTAG, and theoretically USB (the data lines are swapped for this, and would need to be fixed with a knife and soldering iron)

MQTT Topics[edit | edit source]

Commands[edit | edit source]


Topic	Arguments	Description
`/projector-controller/cmd/power`	ON/OFF	Sends the main power commands
`/projector-controller/cmd/(menu\|enter\|up\|down\|left\|right\|back)`		Emulate keypresses
`/projector-controller/cmd/raw`	Binary data	Sends raw bytes over serial, framed with `[0x02, [...data] 0x03]`

Status[edit | edit source]


Topic	Values	Description
`/projector-controller/availability`	online/(offline)	Publishes the controller's availability every couple of seconds
`/projector-controller/stat/power`	ON/OFF	Publishes the projector's power status (doesn't work)

Limitations[edit | edit source]

There is a QPW command for querying its current power status, the projector only responds sometimes though.

References[edit | edit source]

@@ Line 9: / Line 9: @@
 |annoying=notify
 |has label=Yes
 |git=https://github.com/chaosdorf/projector-controller-iot}}Controls the [[Beamer Hackcenter|projector]] via its RS232 interface. Integrated into [[HomeAssistant]] via MQTT.
 === Location ===
@@ Line 18: / Line 18: @@
 Programmable via UART, JTAG, and theoretically USB (the data lines are swapped for this, and would need to be fixed with a knife and soldering iron)
+==== MQTT Topics ====
+===== Commands =====
+{| class="wikitable sortable"
+|+
+!Topic
+!Arguments
+!Description
+|-
+|<code>/projector-controller/cmd/power</code>
+|ON/OFF
+|Sends the main power commands
+|-
+|<code><nowiki>/projector-controller/cmd/(menu|enter|up|down|left|right|back)</nowiki></code>
+|
+|Emulate keypresses
+|-
+|<code>/projector-controller/cmd/raw</code>
+|Binary data
+|Sends raw bytes over serial, framed with <code>[0x02, [...data] 0x03]</code>
+|}
+===== Status =====
+{| class="wikitable sortable"
+|+
+!Topic
+!Values
+!Description
+|-
+|<code>/projector-controller/availability</code>
+|online/(offline)
+|Publishes the controller's availability every couple of seconds
+|-
+|<code>/projector-controller/stat/power</code>
+|ON/OFF
+|Publishes the projector's power status '''(doesn't work)'''
+|}
 == Limitations ==
-When the projector receives an invalid command—e. g. ''power on'' when it's already powered on—it just ignores all future commands until the serial cable is yanked and replugged. There is a <code>QPW</code> command for querying its current power status, the projector just does not seem to respond to it in the way mentioned in the manual.<ref>https://web.archive.org/web/20171028162105/http://www.projectorcentral.com/pdf/projector_manual_6589.pdf</ref>
+There is a <code>QPW</code> command for querying its current power status, the projector only responds sometimes though.
 == References ==