diff --git a/recipes/.gitignore b/recipes/.gitignore
index e5730d0..f10dad4 100644
--- a/recipes/.gitignore
+++ b/recipes/.gitignore
@@ -3,4 +3,5 @@
 *.hex
 *.obj
 *.rom
+*.8xu
 *.sms
diff --git a/recipes/ti84/Makefile b/recipes/ti84/Makefile
index ca7ed63..b1338a0 100644
--- a/recipes/ti84/Makefile
+++ b/recipes/ti84/Makefile
@@ -1,6 +1,7 @@
 TARGET = os.rom
 ZASM = ../../tools/zasm.sh
 KERNEL = ../../kernel
+MKTIUPGRADE = mktiupgrade
 
 .PHONY: all
 all: $(TARGET)
@@ -8,3 +9,9 @@ $(TARGET): glue.asm
 	$(ZASM) $(KERNEL) < $< > $@
 	truncate -s 1M $@
 
+os.8xu: $(TARGET)
+	$(MKTIUPGRADE) -p -k keys/0A.key -d TI-84+ $< $@ 00
+
+.PHONY: send
+send: os.8xu
+	tilp -n --calc ti84+ --cable DirectLink $<
diff --git a/recipes/ti84/README.md b/recipes/ti84/README.md
index 3023662..b83d737 100644
--- a/recipes/ti84/README.md
+++ b/recipes/ti84/README.md
@@ -29,4 +29,29 @@ Collapse OS prompt will appear.
 
 ## Upload to the calculator
 
-TODO
+**WARNING: the instructions below will wipe all the contents of your calculator,
+including TI-OS.**
+
+To send your ROM to the calculator, you'll need two more tools:
+[mktiupgrade][mktiupgrade] and [tilp][tilp].
+
+Once you have them, you need to place your calculator in "bootloader mode",
+that is, in a mode where it's ready to receive a new binary from its USB cable.
+To do that you need to:
+
+1. Shut down the calculator by removing one of the battery.
+2. Hold the DEL key
+3. But the battery back.
+4. A "Waiting... Please install operating system now" message will appear.
+
+Once this is done, you can plug the USB cable in your computer and run
+`make send`. This will create an "upgrade file" with `mktiupgrade` and then
+push that upgrade file with `tilp`. `tilp` will prompt you at some point.
+Press "1" to continue.
+
+When this is done, you can press the ON button to see Collapse OS' prompt!
+
+[knightos]: https://knightos.org/
+[z80e]: https://github.com/KnightOS/z80e
+[mktiupgrade]: https://github.com/KnightOS/mktiupgrade
+[tilp]: http://lpg.ticalc.org/prj_tilp/
diff --git a/recipes/ti84/keys/02.key b/recipes/ti84/keys/02.key
new file mode 100644
index 0000000..de47716
--- /dev/null
+++ b/recipes/ti84/keys/02.key
@@ -0,0 +1,3 @@
+4081396D55C0989BC949FA30821FFE61C9441EDC3827D0E89EEE16DDEF697634B8E10B8B7F42FE7CC1A7478606D6D09F6FE96365E71E3D2AAA7C8D91068F1DFAF3
+20E1A6FD4557AB2234E92FACBBADD9E7FA2452B5C238F1EF296AFB2BFE67BACC1E
+21A106BE04DC99B4F389D3B96951224E064F417E34EEF53130E9BEDC9A721EE1EB07
diff --git a/recipes/ti84/keys/04.key b/recipes/ti84/keys/04.key
new file mode 100644
index 0000000..6624af4
--- /dev/null
+++ b/recipes/ti84/keys/04.key
@@ -0,0 +1,3 @@
+408FE528B340EB1C88B505B2354BAADF47F3616D92CB532E7E5A2A0DFF1C4E4283CEEA2B2F7AD5F28B7E4BE4F3F4C99CABA0D98A8E5F2BE15E2AAC7CED0940EF82
+20CDFF9610024DB1B7AD46D691E0E538BB00A1D840F5CCAF8EC0FED20C3A9D700B
+21CB4662A9084F5076B117892EBA3FB0DF9EB24988A62A83890B5A0B4E18BD07720B
diff --git a/recipes/ti84/keys/0A.key b/recipes/ti84/keys/0A.key
new file mode 100644
index 0000000..53e7a32
--- /dev/null
+++ b/recipes/ti84/keys/0A.key
@@ -0,0 +1,3 @@
+40B11C71D4EA2C13C9AB2E501C6085FEC87FF3B88BFD783EAC43351E1B10F65AD31C79C1268F75051DC8FC008EBF593AE5912E8B653975C13127E2B60A0BEF5FEF
+204DD5B4E544CACBC4EF869CDA30A6908FF7D1BDDB92B1ADE1E1C93CC614904894
+21F5E2DFBCA3D5C86F4815DC69452E4FC7D122D650374E880B62294279F21A439D01
diff --git a/recipes/ti84/keys/0F.key b/recipes/ti84/keys/0F.key
new file mode 100644
index 0000000..53e7a32
--- /dev/null
+++ b/recipes/ti84/keys/0F.key
@@ -0,0 +1,3 @@
+40B11C71D4EA2C13C9AB2E501C6085FEC87FF3B88BFD783EAC43351E1B10F65AD31C79C1268F75051DC8FC008EBF593AE5912E8B653975C13127E2B60A0BEF5FEF
+204DD5B4E544CACBC4EF869CDA30A6908FF7D1BDDB92B1ADE1E1C93CC614904894
+21F5E2DFBCA3D5C86F4815DC69452E4FC7D122D650374E880B62294279F21A439D01