diff --git a/src/jtag/drivers/cmsis_dap.c b/src/jtag/drivers/cmsis_dap.c
index 06d5c6962..9bd4cb73a 100644
--- a/src/jtag/drivers/cmsis_dap.c
+++ b/src/jtag/drivers/cmsis_dap.c
@@ -2004,7 +2004,7 @@ COMMAND_HANDLER(cmsis_dap_handle_cmd_command)
 	uint8_t *command = cmsis_dap_handle->command;
 
 	for (unsigned i = 0; i < CMD_ARGC; i++)
-		command[i] = strtoul(CMD_ARGV[i], NULL, 16);
+		COMMAND_PARSE_NUMBER(u8, CMD_ARGV[i], command[i]);
 
 	int retval = cmsis_dap_xfer(cmsis_dap_handle, CMD_ARGC);
 
diff --git a/src/jtag/drivers/cmsis_dap_usb_bulk.c b/src/jtag/drivers/cmsis_dap_usb_bulk.c
index cb3e02fe2..26c6784f9 100644
--- a/src/jtag/drivers/cmsis_dap_usb_bulk.c
+++ b/src/jtag/drivers/cmsis_dap_usb_bulk.c
@@ -464,7 +464,7 @@ static int cmsis_dap_usb_alloc(struct cmsis_dap *dap, unsigned int pkt_sz)
 COMMAND_HANDLER(cmsis_dap_handle_usb_interface_command)
 {
 	if (CMD_ARGC == 1)
-		cmsis_dap_usb_interface = strtoul(CMD_ARGV[0], NULL, 10);
+		COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], cmsis_dap_usb_interface);
 	else
 		LOG_ERROR("expected exactly one argument to cmsis_dap_usb_interface <interface_number>");