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authorMatt Harvey <[email protected]>2020-09-14 14:49:57 -0700
committerGitHub <[email protected]>2020-09-14 14:49:57 -0700
commit6781ac00366e2c46c0a4ed18dfd60e41a3fa4ae6 (patch)
tree942fd44b1f9d20de7ee8cbf473470874bf43f03c
parent79899c747970f7b7e1cd69f714e2146621727bc5 (diff)
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Corrects order of UART RX/TX interrupt enable bits
(per http://byterunner.com/16550.html and manually tested in qemu bare metal echo)
-rw-r--r--kernel/uart.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/uart.c b/kernel/uart.c
index ce89615..d586ea4 100644
--- a/kernel/uart.c
+++ b/kernel/uart.c
@@ -22,8 +22,8 @@
#define RHR 0 // receive holding register (for input bytes)
#define THR 0 // transmit holding register (for output bytes)
#define IER 1 // interrupt enable register
-#define IER_TX_ENABLE (1<<0)
-#define IER_RX_ENABLE (1<<1)
+#define IER_RX_ENABLE (1<<0)
+#define IER_TX_ENABLE (1<<1)
#define FCR 2 // FIFO control register
#define FCR_FIFO_ENABLE (1<<0)
#define FCR_FIFO_CLEAR (3<<1) // clear the content of the two FIFOs